Lamin A reassembly at the end of mitosis is regulated by its SUMO-interacting motif
DOE Office of Scientific and Technical Information (OSTI.GOV)
Moriuchi, Takanobu; Kuroda, Masaki; Kusumoto, Fumiya
Modification of proteins with small ubiquitin-related modifier (SUMO; SUMOylation) is involved in the regulation of various biological processes. Recent studies have demonstrated that noncovalent associations between SUMOylated proteins and co-operative proteins containing SUMO-interacting motifs (SIMs) are important for the spatiotemporal organization of many protein complexes. In this study, we demonstrate that interactions between lamin A, a major component of the nuclear lamina, and SUMO isoforms are dependent on one of the four SIMs (SIM3) resided in lamin A polypeptide in vitro. Live cell imaging and immunofluorescence staining showed that SIM3 is required for accumulation of lamin A on the chromosomesmore » during telophase, and subsequent evaluation of a panel of deletion mutants determined that a 156-amino acid region spanning the carboxyl-terminal Ig-fold domain of lamin A is sufficient for this accumulation. Notably, mutation of SIM3 abrogated the dephosphorylation of mitosis-specific phosphorylation at Ser-22 of lamin A, which normally occurs during telophase, and the subsequent nuclear lamina reorganization. Furthermore, expression of a conjugation-defective SUMO2 mutant, which was previously shown to inhibit endogenous SUMOylation in a dominant-negative manner, also impaired the accumulation of wild type lamin A on telophase chromosomes. These findings suggest that interactions between SIM3 of lamin A and a putative SUMO2-modified protein plays an important role in the reorganization of the nuclear lamina at the end of mitosis. - Highlights: • Lamin A interacts with SUMO2 via a SUMO-interacting motif (SIM) in the Ig domain. • SIM3 of lamin A is responsible for chromosomal accumulation during telophase. • A 156-aa region spanning the Ig domain is sufficient for chromosomal accumulation. • Accumulation of lamin A is required for timely dephosphorylation on chromosomes. • A putative SUMO2-modified protein may mediate chromosomal accumulation of lamin A.« less
Zimmermann, K; Herget, T; Salbaum, J M; Schubert, W; Hilbich, C; Cramer, M; Masters, C L; Multhaup, G; Kang, J; Lemaire, H G
1988-01-01
Cloning and sequence analysis revealed the putative amyloid A4 precursor (pre-A4) of Alzheimer's disease to have characteristics of a membrane-spanning glycoprotein. In addition to brain, pre-A4 mRNA was found in adult human muscle and other tissues. We demonstrate by in situ hybridization that pre-A4 mRNA is present in adult human muscle, in cultured human myoblasts and myotubes. Immunofluorescence with antipeptide antibodies shows the putative pre-A4 protein to be expressed in adult human muscle and associated with some but not all nuclear envelopes. Despite high levels of a single 3.5-kb pre-A4 mRNA species in cultured myoblasts and myotubes, the presence of putative pre-A4 protein could not be detected by immunofluorescence. This suggests that putative pre-A4 protein is stabilized and therefore functioning in the innervated muscle tissue but not in developing, i.e. non-innervated cultured muscle cells. The selective localization of the protein on distinct nuclear envelopes could reflect an interaction with motor endplates. Images PMID:2896589
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Xuan; Miller, Elliot N.; Yomano, Lorraine P.
The subject invention pertains to overexpression of a putative oxidoreductase (ucpA) for increasing furfural tolerance in genetically modified microorganisms. Genetically modified microorganisms capable of overexpressing UcpA are also provided. Increased expression of ucpA was shown to increase furfural tolerance by 50%, and to permit the fermentation of sugars to products in the presence of 15 mM furfural.
Pinarbasi, Emile S; Cağatay, Tolga; Fung, Ho Yee Joyce; Li, Ying C; Chook, Yuh Min; Thomas, Philip J
2018-05-04
ALS (Amyotrophic Lateral Sclerosis) is a neurodegenerative disease characterized by the redistribution of the RNA binding protein TDP-43 in affected neurons: from predominantly nuclear to aggregated in the cytosol. However, the determinants of TDP-43 localization and the cellular insults that promote redistribution are incompletely understood. Here, we show that the putative Nuclear Export Signal (NES) is not required for nuclear egress of TDP-43. Moreover, when the TDP-43 domain which contains the putative NES is fused to a reporter protein, YFP, the presence of the NES is not sufficient to mediate nuclear exclusion of the fusion protein. We find that the previously studied "∆NES" mutant, in which conserved hydrophobic residues are mutated to alanines, disrupts both solubility and splicing function. We further show that nuclear export of TDP-43 is independent of the exportin XPO1. Finally, we provide evidence that nuclear egress of TDP-43 is size dependent; nuclear export of dTomato TDP-43 is significantly impaired compared to Flag TDP-43. Together, these results suggest nuclear export of TDP-43 is predominantly driven by passive diffusion.
Jóri, Balazs; Kamps, Rick; Xanthoulea, Sofia; Delvoux, Bert; Blok, Marinus J; Van de Vijver, Koen K; de Koning, Bart; Oei, Felicia Trups; Tops, Carli M; Speel, Ernst Jm; Kruitwagen, Roy F; Gomez-Garcia, Encarna B; Romano, Andrea
2015-12-01
The risk to develop colorectal and endometrial cancers among subjects testing positive for a pathogenic Lynch syndrome mutation varies, making the risk prediction difficult. Genetic risk modifiers alter the risk conferred by inherited Lynch syndrome mutations, and their identification can improve genetic counseling. We aimed at identifying rare genetic modifiers of the risk of Lynch syndrome endometrial cancer. A family based approach was used to assess the presence of genetic risk modifiers among 35 Lynch syndrome mutation carriers having either a poor clinical phenotype (early age of endometrial cancer diagnosis or multiple cancers) or a neutral clinical phenotype. Putative genetic risk modifiers were identified by Next Generation Sequencing among a panel of 154 genes involved in endometrial physiology and carcinogenesis. A simple pipeline, based on an allele frequency lower than 0.001 and on predicted non-conservative amino-acid substitutions returned 54 variants that were considered putative risk modifiers. The presence of two or more risk modifying variants in women carrying a pathogenic Lynch syndrome mutation was associated with a poor clinical phenotype. A gene-panel is proposed that comprehends genes that can carry variants with putative modifying effects on the risk of Lynch syndrome endometrial cancer. Validation in further studies is warranted before considering the possible use of this tool in genetic counseling.
Prm3p is a pheromone-induced peripheral nuclear envelope protein required for yeast nuclear fusion.
Shen, Shu; Tobery, Cynthia E; Rose, Mark D
2009-05-01
Nuclear membrane fusion is the last step in the mating pathway of the yeast Saccharomyces cerevisiae. We adapted a bioinformatics approach to identify putative pheromone-induced membrane proteins potentially required for nuclear membrane fusion. One protein, Prm3p, was found to be required for nuclear membrane fusion; disruption of PRM3 caused a strong bilateral defect, in which nuclear congression was completed but fusion did not occur. Prm3p was localized to the nuclear envelope in pheromone-responding cells, with significant colocalization with the spindle pole body in zygotes. A previous report, using a truncated protein, claimed that Prm3p is localized to the inner nuclear envelope. Based on biochemistry, immunoelectron microscopy and live cell microscopy, we find that functional Prm3p is a peripheral membrane protein exposed on the cytoplasmic face of the outer nuclear envelope. In support of this, mutations in a putative nuclear localization sequence had no effect on full-length protein function or localization. In contrast, point mutations and deletions in the highly conserved hydrophobic carboxy-terminal domain disrupted both protein function and localization. Genetic analysis, colocalization, and biochemical experiments indicate that Prm3p interacts directly with Kar5p, suggesting that nuclear membrane fusion is mediated by a protein complex.
Evidence for triclosan-induced activation of human and rodent xenobiotic nuclear receptors
The bacteriostat triclosan (2,4,40-trichloro-20-hydroxydiphenylether) (TCS) decreases rat serum thyroxine via putative nuclear receptor (NR) interaction(s) and subsequent transcriptional up-regulation of hepatic catabolism and clearance. However, due to the evolutionary divergenc...
Nuclear localization of Klotho in brain: an anti-aging protein
German, Dwight C.; Khobahy, Ida; Pastor, Johanne; Kuro-o, Makoto; Liu, Xinran
2011-01-01
Klotho is a putative age-suppressing gene whose over-expression in mice results in extension of life span. The klotho gene encodes a single-pass transmembrane protein whose extracellular domain is shed and released into blood, urine, and cerebrospinal fluid, potentially functioning as a humoral factor. The extracellular domain of Klotho has an activity that increases the expression of anti-oxidant enzymes and confers resistance to oxidative stress in cultured cells and in whole animals. The transmembrane form of the Klotho protein directly binds to multiple fibroblast growth factor receptors and modifies their ligand affinity and specificity. The purpose of the present study was to determine the precise cellular localization of Klotho in the mouse brain. Using light microscopic immunohistochemical methods, we found the highest levels of Klotho immunoreactivity in two brain regions: the choroid plexus, and cerebellar Purkinje cells. In the choroid plexus cells, Klotho was found not only on the plasma membrane but also in large amounts near the nuclear membrane. Likewise, in the Purkinje cell Klotho was found throughout the cell including dendrites, axon and soma with large amounts near the nuclear membrane. Using immunoelectron microscopy, we found Klotho in the cell membrane, but the highest concentration was localized in the peripheral portion of the nucleus and the nucleolus in both cell types. This new finding suggests that in addition to Klotho being secreted from cells in brain, it also has a nuclear function. PMID:22245317
Gravett, Nadine; Bhagwandin, Adhil; Fuxe, Kjell; Manger, Paul R
2009-09-01
The nuclear subdivisions of the cholinergic, putative catecholaminergic and serotonergic systems within the brain of the rock hyrax (Procavia capensis) were identified following immunohistochemistry for acetylcholinesterase, tyrosine hydroxylase and serotonin. The aim of the present study was to investigate possible differences in the complement of nuclear subdivisions of these systems by comparing those of the rock hyrax to published studies of other mammals. The rock hyrax belongs to the order Hyracoidea and forms part of the Afroplacentalia mammalian cohort. For the most part, the nuclear organization of these three systems closely resembled that described for many other mammalian species. The nuclear organization of the serotonergic system was identical to that seen in all eutherian mammals. The nuclear organization of the putative catecholaminergic system was very similar to that seen in rodents except for the lack of a C3 nucleus and the compact division of the locus coeruleus (A6c). In addition, the diffuse locus coeruleus (A6d) appeared to contain very few tyrosine hydroxylase immunoreactive (TH+) neurons. The cholinergic system showed many features in common with that seen in both rodents and primates; however, there were three differences of note: (1) cholinergic neurons were observed in the anterior nuclei of the dorsal thalamus; (2) cholinergic parvocellular nerve cells, probably representing interneurons, forming subdivisions of the laterodorsal and pedunculopontine tegmental nuclei were observed at the midbrain/pons interface; and (3) a large number of cholinergic nerve cells in the periventricular grey of the medulla oblongata were observed. Thus, while there are many similarities to other mammalian species, the nuclear organization of these systems in the rock hyrax shows specific differences to what has been observed previously in other mammals. These differences are discussed in both a functional and phylogenetic perspective.
Scarpari, Leandra M; Lambais, Marcio R; Silva, Denise S; Carraro, Dirce M; Carrer, Helaine
2003-05-16
Xylella fastidiosa is the causal agent of economically important plant diseases, including citrus variegated chlorosis and Pierce's disease. Hitherto, there has been no information on the molecular mechanisms controlling X. fastidiosa-plant interactions. To determine whether predicted open reading frames (ORFs) encoding putative pathogenicity-related factors were expressed by X. fastidiosa 9a5c cells grown at low (LCD) and high cell density (HCD) conditions in liquid modified PW medium, reverse Northern blot hybridization and reverse transcription-polymerase chain reaction (RT-PCR) experiments were performed. Our results indicated that ORFs XF2344, XF2369, XF1851 and XF0125, encoding putative Fur, GumC, a serine-protease and RsmA, respectively, were significantly suppressed at HCD conditions. In contrast, ORF XF1115, encoding putative RpfF, was significantly induced at HCD conditions. Expressions of ORFs XF2367, XF2362 and XF0290, encoding putative GumD, GumJ and RpfA, respectively, were detected only at HCD conditions, whereas expression of ORF XF0287, encoding putative RpfB was detected only at LCD conditions. Bioassays with an Agrobacterium traG::lacZ reporter system indicated that X. fastidiosa does not synthesize N-acyl-homoserine lactones, whereas bioassays with a diffusible signal factor (DSF)-responsive Xanthomonas campestris pv. campestris mutant indicate that X. fastidiosa synthesizes a molecule similar to DSF in modified PW medium. Our data also suggest that the synthesis of the DSF-like molecule and fastidian gum by X. fastidiosa is affected by cell density in vitro.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wanitchang, Asawin; Narkpuk, Jaraspim; Jongkaewwattana, Anan, E-mail: anan.jon@biotec.or.th
The nucleoprotein of influenza B virus (BNP) shares several characteristics with its influenza A virus counterpart (ANP), including localization in the host's nucleus. However, while the nuclear localization signal(s) (NLS) of ANP are well characterized, little is known about those of BNP. In this study, we showed that the fusion protein bearing the BNP N-terminus fused with GFP (N70–GFP) is exclusively nuclear, and identified a highly conserved KRXR motif spanning residues 44–47 as a putative NLS. In addition, we demonstrated that residues 3–15 of BNP, though not an NLS, are also crucial for nuclear import. Results from mutational analyses ofmore » N70–GFP and the full-length BNP suggest that this region may be required for protection of the N-terminus from proteolytic cleavage. Altogether, we propose that the N-terminal region of BNP contains the NLS and cleavage-protection motif, which together drive its nuclear localization. - Highlights: • The N-terminal region of BNP is required for nuclear accumulation. • The conserved motif at position 44–47 is a putative nuclear localization signal. • The first 15 amino acids of BNP may function as a cleavage-protection motif. • BNP may get access to the nucleus via a mechanism distinct from ANP.« less
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2012-06-18
... Atomic Electric Company, Yankee Nuclear Power Station, Confirmatory Order Modifying License (Effective... of 10 CFR part 72, Subpart K at the Yankee Nuclear Power Station. The facility is located at the... Facility Operating License for Yankee Nuclear Power Station must be modified to include provisions with...
Role of the putative structural protein Sed1p in mitochondrial genome maintenance.
Phadnis, Naina; Ayres Sia, Elaine
2004-09-24
The nuclear gene MIP1 encodes the mitochondrial DNA polymerase responsible for replicating the mitochondrial genome in Saccharomyces cerevisiae. A number of other factors involved in replicating and segregating the mitochondrial genome are yet to be identified. Here, we report that a bacterial two-hybrid screen using the mitochondrial polymerase, Mip1p, as bait identified the yeast protein Sed1p. Sed1p is a cell surface protein highly expressed in the stationary phase. We find that several modified forms of Sed1p are expressed and the largest of these forms interacts with the mitochondrial polymerase in vitro. Deletion of SED1 causes a 3.5-fold increase in the rate of mitochondrial DNA point mutations as well as a 4.3-fold increase in the rate of loss of respiration. In contrast, we see no change in the rate of nuclear point mutations indicating the specific role of Sed1p function in mitochondrial genome stability. Indirect immunofluorescence analysis of Sed1p localization shows that Sed1p is targeted to the mitochondria. Moreover, Sed1p is detected in purified mitochondrial fractions and the localization to the mitochondria of the largest modified form is insensitive to the action of proteinase K. Deletion of the sed1 gene results in a reduction in the quantity of Mip1p and also affects the levels of a mitochondrially-expressed protein, Cox3p. Our results point towards a role for Sed1p in mitochondrial genome maintenance.
Bain, Peter A; Papanicolaou, Alexie; Kumar, Anupama
2015-01-01
Murray-Darling rainbowfish (Melanotaenia fluviatilis [Castelnau, 1878]; Atheriniformes: Melanotaeniidae) is a small-bodied teleost currently under development in Australasia as a test species for aquatic toxicological studies. To date, efforts towards the development of molecular biomarkers of contaminant exposure have been hindered by the lack of available sequence data. To address this, we sequenced messenger RNA from brain, liver and gonads of mature male and female fish and generated a high-quality draft transcriptome using a de novo assembly approach. 149,742 clusters of putative transcripts were obtained, encompassing 43,841 non-redundant protein-coding regions. Deduced amino acid sequences were annotated by functional inference based on similarity with sequences from manually curated protein sequence databases. The draft assembly contained protein-coding regions homologous to 95.7% of the complete cohort of predicted proteins from the taxonomically related species, Oryzias latipes (Japanese medaka). The mean length of rainbowfish protein-coding sequences relative to their medaka homologues was 92.1%, indicating that despite the limited number of tissues sampled a large proportion of the total expected number of protein-coding genes was captured in the study. Because of our interest in the effects of environmental contaminants on endocrine pathways, we manually curated subsets of coding regions for putative nuclear receptors and steroidogenic enzymes in the rainbowfish transcriptome, revealing 61 candidate nuclear receptors encompassing all known subfamilies, and 41 putative steroidogenic enzymes representing all major steroidogenic enzymes occurring in teleosts. The transcriptome presented here will be a valuable resource for researchers interested in biomarker development, protein structure and function, and contaminant-response genomics in Murray-Darling rainbowfish.
James M. Slavicek; Nancy Hayes-Plazolles
1991-01-01
Viral immediate early gene products are usually regulatory proteins that control expression of other viral genes at the transcriptional level or are proteins that are part of the viral DNA replication complex. The identification and functional characterization of the immediate early gene products of Lymantria dispar nuclear polyhedrosis virus (LdNPV...
Revisiting the taxonomy of the Rattini tribe: a phylogeny-based delimitation of species boundaries
2010-01-01
Background Rodents are recognized as hosts for at least 60 zoonotic diseases and may represent a serious threat for human health. In the context of global environmental changes and increasing mobility of humans and animals, contacts between pathogens and potential animal hosts and vectors are modified, amplifying the risk of disease emergence. An accurate identification of each rodent at a specific level is needed in order to understand their implications in the transmission of diseases. Among the Muridae, the Rattini tribe encompasses 167 species inhabiting South East Asia, a hotspot of both biodiversity and emerging and re-emerging diseases. The region faces growing economical development that affects habitats, biodiversity and health. Rat species have been demonstrated as significant hosts of pathogens but are still difficult to recognize at a specific level using morphological criteria. DNA-barcoding methods appear as accurate tools for rat species identification but their use is hampered by the need of reliable identification of reference specimens. In this study, we explore and highlight the limits of the current taxonomy of the Rattini tribe. Results We used the DNA sequence information itself as the primary information source to establish group membership and estimate putative species boundaries. We sequenced two mitochondrial and one nuclear genes from 122 rat samples to perform phylogenetic reconstructions. The method of Pons and colleagues (2006) that determines, with no prior expectations, the locations of ancestral nodes defining putative species was then applied to our dataset. To give an appropriate name to each cluster recognized as a putative species, we reviewed information from the literature and obtained sequences from a museum holotype specimen following the ancient DNA criteria. Conclusions Using a recently developed methodology, this study succeeds in refining the taxonomy of one of the most difficult groups of mammals. Most of the species expected within the area were retrieved but new putative species limits were also indicated, in particular within Berylmys and Rattus genera, where future taxonomic studies should be directed. Our study lays the foundations to better investigate rodent-born diseases in South East Asia and illustrates the relevance of evolutionary studies for health and medical sciences. PMID:20565819
Revisiting the taxonomy of the Rattini tribe: a phylogeny-based delimitation of species boundaries.
Pagès, Marie; Chaval, Yannick; Herbreteau, Vincent; Waengsothorn, Surachit; Cosson, Jean-François; Hugot, Jean-Pierre; Morand, Serge; Michaux, Johan
2010-06-18
Rodents are recognized as hosts for at least 60 zoonotic diseases and may represent a serious threat for human health. In the context of global environmental changes and increasing mobility of humans and animals, contacts between pathogens and potential animal hosts and vectors are modified, amplifying the risk of disease emergence. An accurate identification of each rodent at a specific level is needed in order to understand their implications in the transmission of diseases. Among the Muridae, the Rattini tribe encompasses 167 species inhabiting South East Asia, a hotspot of both biodiversity and emerging and re-emerging diseases. The region faces growing economical development that affects habitats, biodiversity and health. Rat species have been demonstrated as significant hosts of pathogens but are still difficult to recognize at a specific level using morphological criteria. DNA-barcoding methods appear as accurate tools for rat species identification but their use is hampered by the need of reliable identification of reference specimens. In this study, we explore and highlight the limits of the current taxonomy of the Rattini tribe. We used the DNA sequence information itself as the primary information source to establish group membership and estimate putative species boundaries. We sequenced two mitochondrial and one nuclear genes from 122 rat samples to perform phylogenetic reconstructions. The method of Pons and colleagues (2006) that determines, with no prior expectations, the locations of ancestral nodes defining putative species was then applied to our dataset. To give an appropriate name to each cluster recognized as a putative species, we reviewed information from the literature and obtained sequences from a museum holotype specimen following the ancient DNA criteria. Using a recently developed methodology, this study succeeds in refining the taxonomy of one of the most difficult groups of mammals. Most of the species expected within the area were retrieved but new putative species limits were also indicated, in particular within Berylmys and Rattus genera, where future taxonomic studies should be directed. Our study lays the foundations to better investigate rodent-born diseases in South East Asia and illustrates the relevance of evolutionary studies for health and medical sciences.
Murakami, Shinya; Kuehnle, Katrin; Stern, David B.
2005-01-01
Numerous nuclear gene products are required for the correct expression of organellar genes. One such gene in the green alga Chlamydomonas reinhardtii is MCD1, whose product is required for stability of the chloroplast-encoded petD mRNA. In mcd1 mutants, which are non-photosynthetic, petD mRNA is degraded by a 5′–3′ exonuclease activity, resulting in a failure to synthesize its product, subunit IV of the cytochrome b 6/f complex. Here, we report the sequence of the wild-type MCD1 gene, which encodes a large and novel putative protein. Analysis of three mutant alleles showed that two harbored large deletions, but that one allele, mcd1-2, had a single base change resulting in a nonsense codon near the N-terminus. This same mutant allele can be suppressed by a second-site mutation in the nuclear MCD2 gene, whereas mcd2-1 cannot suppress the deletion in mcd1-1 (Esposito,D. Higgs,D.C. Drager,R.G. Stern, D.B. and Girard-Bascou,J. (2001) Curr. Genet., 39, 40–48). We report the cloning of mcd2-1, and show that the mutation lies in a tRNASer(CGA), which has been modified to translate the nonsense codon in mcd1-2. We discuss how the existence of a large tRNASer gene family may permit this suppression without pleiotropic consequences. PMID:15947135
NASA Astrophysics Data System (ADS)
Smolyanskii, A. S.; Kozlova, N. V.; Zheltova, A. V.; Aksyutina, A. S.; Shvedov, A. S.; Lakeev, S. G.
2015-07-01
Light scattering and interference patterns are studied in the optical absorption spectra of nuclear filters based on polyethylene terephthalate fi lms modifi ed by dry aerosol deposition of silver nano- and microparticles. Surface plasmon polaritons and localized plasmons formed by the passage of light through porous silver films are found to have an effect on the diffraction and interference modes. The thickness of silver nano- and microparticle coatings on the surface of the nuclear fi lters was determined from the shift in the interference patterns in the optical absorption spectra of the modified nuclear filters relative to the original nuclear filters. A correlation was found between the estimated coating thickness and the average surface roughness of the nuclear filters modified by layers of silver nano- and microparticles.
Bux, Faiza; Bhagwandin, Adhil; Fuxe, Kjell; Manger, Paul R
2010-05-01
The current study describes the nuclear organization and neuronal morphology of the cholinergic, putative catecholaminergic and serotonergic systems within the diencephalon, midbrain and pons of the giraffe using immunohistochemistry for choline acetyltransferase, tyrosine hydroxylase and serotonin. The giraffe has a unique phenotype (the long neck), a large brain (over 500 g) and is a non-domesticated animal, while previous studies examining the brains of other Artiodactyls have all been undertaken on domesticated animals. The aim of the present study was to investigate possible differences in the nuclear organization and neuronal morphology of the above-mentioned systems compared to that seen in other Artiodactyls and mammals. The nuclear organization of all three systems within the giraffe brain was similar to that of other Artiodactyls. Some features of interest were noted for the giraffe and in comparison to other mammals studied. The cholinergic neuronal somata of the laterodorsal tegmental nucleus were slightly larger than those of the pedunculopontine tegmental nucleus, a feature not described in other mammals. The putative catecholaminergic system of the giraffe appeared to lack an A15 dorsal nucleus, which is commonly seen in other mammals but absent in the Artiodactyls, had a large and expanded substantia nigra pars reticulata (A9 ventral), a small diffuse portion of the locus coerueleus (A6d), an expansive subcoeruleus (A7sc and A7d), and lacked the A4 nucleus of the locus coeruleus complex. The nuclear organization of the serotonergic system of the giraffe was identical to that seen in all other eutherian mammals studied to date. These observations in the giraffe demonstrate that despite significant changes in life history, phenotype, brain size and time of divergence, species within the same order show the same nuclear organization of the systems investigated. Copyright (c) 2009 Elsevier B.V. All rights reserved.
Kim, Eunhye; Hwang, Seon-Ung; Yoo, Hyunju; Yoon, Junchul David; Jeon, Yubyeol; Kim, Hyunggee; Jeung, Eui-Bae; Lee, Chang-Kyu; Hyun, Sang-Hwan
2016-03-01
The establishment of porcine embryonic stem cells (ESCs) would have great impact in biomedical studies and preclinical trials through their use in genetic engineering. However, authentic porcine ESCs have not been established until now. In this study, a total of seven putative ESC lines were derived from porcine embryos of various origins, including in vitro fertilization, parthenogenetic activation, and, in particular, induced pluripotent stem (iPS) nuclear transfer (NT) from a donor cell with induced pluripotent stem cells (iPSCs). To characterize these cell lines, several assays including an assessment of intensive alkaline phosphatase activity, karyotyping, embryoid body formation, expression analysis of the pluripotency-associated markers, and the three germ layerassociated markers were performed. Based on quantitative polymerase chain reaction, the expression levels of REX1 and FGFR2 in iPS-NT lines were higher than those of cells of other origins. Additionally, only iPS-NT lines showed multiple aberrant patterns of nuclear foci elucidated by immunofluorescence staining of H3K27me3 as a marker of the state of X chromosome inactivation and a less mature form of mitochondria like naive ESCs, by transmission electron microscopy. Together, these data suggested that established putative porcine ESC lines generally exhibited a primed pluripotent state, like human ESCs. However, iPS-NT lines have especially unique characteristics distinct from other origins because they have more epigenetic instability and naive-like mitochondrial morphology than other putative ESC lines. This is the first study to establish and characterize the iPSC-derived putative ESC lines and compare them with other lines derived from different origins in pigs. Copyright © 2016 Elsevier Inc. All rights reserved.
The scope of phage display for membrane proteins.
Vithayathil, Rosemarie; Hooy, Richard M; Cocco, Melanie J; Weiss, Gregory A
2011-12-09
Numerous examples of phage display applied to soluble proteins demonstrate the power of the technique for protein engineering, affinity reagent discovery and structure-function studies. Recent reports have expanded phage display to include membrane proteins (MPs). The scope and limitations of MP display remain undefined. Therefore, we report data from the phage display of representative types of membrane-associated proteins including plasma, nuclear, peripheral, single and multipass. The peripheral MP neuromodulin displays robustly with packaging by conventional M13-KO7 helper phage. The monotopic MP Nogo-66 can also display on the phage surface, if packaged by the modified M13-KO7(+) helper phage. The modified phage coat of KO7(+) can better mimic the zwitterionic character of the plasma membrane. Four examples of putatively α-helical, integral MPs failed to express as fusions to an anchoring phage coat protein and therefore did not display on the phage surface. However, the β-barrel MPs ShuA (Shigella heme uptake A) and MOMP (major outer membrane protein), which pass through the membrane 22 and 16 times, respectively, can display surprisingly well on the surfaces of both conventional and KO7(+) phages. The results provide a guide for protein engineering and large-scale mutagenesis enabled by the phage display of MPs. Copyright © 2011 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chakrabarti, Rajarshi; Bhowmick, Debajit; Bhargava, Varsha
2013-09-20
Highlights: •Nuclear pool of PIP5K is SUMOylated. •Enhancement of SUMOylated nuclear PIP5K during apoptosis. •Nuclear PIP5K is modified by polySUMO-1 during apoptosis. •Nuclear PIP5K is modified by polySUMO-2 chain during apoptosis. -- Abstract: Phosphatidylinositol 4 phosphate 5 kinase 1α (PIP5K) is mainly localized in the cytosol and plasma membrane. Studies have also indicated its prominent association with nuclear speckles. The exact nature of this nuclear pool of PIP5K is not clear. Using biochemical and microscopic techniques, we have demonstrated that the nuclear pool of PIP5K is modified by SUMO-1 in HEK-293 cells stably expressing PIP5K. Moreover, this SUMOylated pool ofmore » PIP5K increased during apoptosis. PolySUMO-2 chain conjugated PIP5K was detected by pull-down experiment using affinity-tagged RNF4, a polySUMO-2 binding protein, during late apoptosis.« less
Leavitt, Dean H; Starrett, James; Westphal, Michael F; Hedin, Marshal
2015-10-01
We use mitochondrial and multi-locus nuclear DNA sequence data to infer both species boundaries and species relationships within California nemesiid spiders. Higher-level phylogenetic data show that the California radiation is monophyletic and distantly related to European members of the genus Brachythele. As such, we consider all California nemesiid taxa to belong to the genus Calisoga Chamberlin, 1937. Rather than find support for one or two taxa as previously hypothesized, genetic data reveal Calisoga to be a species-rich radiation of spiders, including perhaps dozens of species. This conclusion is supported by multiple mitochondrial barcoding analyses, and also independent analyses of nuclear data that reveal general genealogical congruence. We discovered three instances of sympatry, and genetic data indicate reproductive isolation when in sympatry. An examination of female reproductive morphology does not reveal species-specific characters, and observed male morphological differences for a subset of putative species are subtle. Our coalescent species tree analysis of putative species lays the groundwork for future research on the taxonomy and biogeographic history of this remarkable endemic radiation. Copyright © 2015 Elsevier Inc. All rights reserved.
Roswitha Schmickl; Aaron Liston; Vojtěch Zeisek; Kenneth Oberlander; Kevin Weitemier; Shannon C. K. Straub; Richard C. Cronn; Léanne L. Dreyer; Jan Suda
2016-01-01
Phylogenetics benefits from using a large number of putatively independent nuclear loci and their combination with other sources of information, such as the plastid and mitochondrial genomes. To facilitate the selection of orthologous low-copy nuclear (LCN) loci for phylogenetics in nonmodel organisms, we created an automated and interactive script to select hundreds...
Characterization of sequences in human TWIST required for nuclear localization
Singh, Shalini; Gramolini, Anthony O
2009-01-01
Background Twist is a transcription factor that plays an important role in proliferation and tumorigenesis. Twist is a nuclear protein that regulates a variety of cellular functions controlled by protein-protein interactions and gene transcription events. The focus of this study was to characterize putative nuclear localization signals (NLSs) 37RKRR40 and 73KRGKK77 in the human TWIST (H-TWIST) protein. Results Using site-specific mutagenesis and immunofluorescences, we observed that altered TWISTNLS1 K38R, TWISTNLS2 K73R and K77R constructs inhibit nuclear accumulation of H-TWIST in mammalian cells, while TWISTNLS2 K76R expression was un-affected and retained to the nucleus. Subsequently, co-transfection of TWIST mutants K38R, K73R and K77R with E12 formed heterodimers and restored nuclear localization despite the NLSs mutations. Using a yeast-two-hybrid assay, we identified a novel TWIST-interacting candidate TCF-4, a basic helix-loop-helix transcription factor. The interaction of TWIST with TCF-4 confirmed using NLS rescue assays, where nuclear expression of mutant TWISTNLS1 with co-transfixed TCF-4 was observed. The interaction of TWIST with TCF-4 was also seen using standard immunoprecipitation assays. Conclusion Our study demonstrates the presence of two putative NLS motifs in H-TWIST and suggests that these NLS sequences are functional. Furthermore, we identified and confirmed the interaction of TWIST with a novel protein candidate TCF-4. PMID:19534813
Expanding the Definition of the Classical Bipartite Nuclear Localization Signal
Lange, Allison; McLane, Laura M.; Mills, Ryan E.; Devine, Scott E.; Corbett, Anita H.
2010-01-01
Nuclear localization signals (NLSs) are amino acid sequences that target cargo proteins into the nucleus. Rigorous characterization of NLS motifs is essential to understanding and predicting pathways for nuclear import. The best-characterized NLS is the classical NLS (cNLS), which is recognized by the cNLS receptor, importin-α. cNLSs are conventionally defined as having one (monopartite) or two clusters of basic amino acids separated by a 9-12 amino acid linker (bipartite). Motivated by the finding that Ty1 integrase, which contains an unconventional putative bipartite cNLS with a 29 amino acid linker, exploits the classical nuclear import machinery, we assessed the functional boundaries for linker length within a bipartite cNLS. We confirmed that the integrase cNLS is a bona fide bipartite cNLS, then carried out a systematic analysis of linker length in an obligate bipartite cNLS cargo, which revealed that some linkers longer than conventionally defined can function in nuclear import. Linker function is dependent on the sequence and likely the inherent flexibility of the linker. Subsequently, we interrogated the Saccharomyces cerevisiae proteome to identify cellular proteins containing putative long bipartite cNLSs. We experimentally confirmed that Rrp4 contains a bipartite cNLS with a 25 amino acid linker. Our studies reveal that the traditional definition of bipartite cNLSs is too restrictive and linker length can vary depending on amino acid composition PMID:20028483
Linking brain imaging and genomics in the study of Alzheimer's disease and aging.
Reiman, Eric M
2007-02-01
My colleagues and I have been using positron emission tomography (PET) and magnetic resonance imaging (MRI) to detect and track the brain changes associated with Alzheimer's disease (AD) and normal brain aging in cognitively normal persons with two copies, one copy, and no copies of the apolipoprotein E (APOE) epsilon4 allele, a common AD susceptibility gene. In this review article, I consider how brain imaging techniques could be used to evaluate putative AD prevention therapies in cognitively normal APOE epsilon4 carriers and putative age-modifying therapies in cognitively normal APOE epsilon4 noncarriers, how they could help investigate the individual and aggregate effects of putative AD risk modifiers, and how they could help guide the investigation of a molecular mechanism associated with AD vulnerability and normal neurological aging. I suggest how high-resolution genome-wide genetic and transcriptomic studies could further help in the scientific understanding of AD, aging, and other common and genetically complex phenotypes, such as variation in normal human memory performance, and in the discovery and evaluation of promising treatments for these phenotypes. Finally, I illustrate the push-pull relationship between brain imaging, genomics research, and other neuroscientific research in the study of AD and aging.
May, Randal; Riehl, Terrence E; Hunt, Clayton; Sureban, Sripathi M; Anant, Shrikant; Houchen, Courtney W
2008-03-01
In the gut, tumorigenesis arises from intestinal or colonic crypt stem cells. Currently, no definitive markers exist that reliably identify gut stem cells. Here, we used the putative stem cell marker doublecortin and CaM kinase-like-1 (DCAMKL-1) to examine radiation-induced stem cell apoptosis and adenomatous polyposis coli (APC)/multiple intestinal neoplasia (min) mice to determine the effects of APC mutation on DCAMKL-1 expression. Immunoreactive DCAMKL-1 staining was demonstrated in the intestinal stem cell zone. Furthermore, we observed apoptosis of the cells negative for DCAMKL-1 at 6 hours. We found DNA damage in all the cells in the crypt region, including the DCAMKL-1-positive cells. We also observed stem cell apoptosis and mitotic DCAMKL-1-expressing cells 24 hours after irradiation. Moreover, in APC/min mice, DCAMKL-1-expressing cells were negative for proliferating cell nuclear antigen and nuclear beta-catenin in normal-appearing intestine. However, beta-catenin was nuclear in DCAMKL-1-positive cells in adenomas. Thus, nuclear translocation of beta-catenin distinguishes normal and adenoma stem cells. Targeting DCAMKL-1 may represent a strategy for developing novel chemotherapeutic agents.
Hypothesis: Gene-rich plastid genomes in red algae may be an outcome of nuclear genome reduction.
Qiu, Huan; Lee, Jun Mo; Yoon, Hwan Su; Bhattacharya, Debashish
2017-06-01
Red algae (Rhodophyta) putatively diverged from the eukaryote tree of life >1.2 billion years ago and are the source of plastids in the ecologically important diatoms, haptophytes, and dinoflagellates. In general, red algae contain the largest plastid gene inventory among all such organelles derived from primary, secondary, or additional rounds of endosymbiosis. In contrast, their nuclear gene inventory is reduced when compared to their putative sister lineage, the Viridiplantae, and other photosynthetic lineages. The latter is thought to have resulted from a phase of genome reduction that occurred in the stem lineage of Rhodophyta. A recent comparative analysis of a taxonomically broad collection of red algal and Viridiplantae plastid genomes demonstrates that the red algal ancestor encoded ~1.5× more plastid genes than Viridiplantae. This difference is primarily explained by more extensive endosymbiotic gene transfer (EGT) in the stem lineage of Viridiplantae, when compared to red algae. We postulate that limited EGT in Rhodophytes resulted from the countervailing force of ancient, and likely recurrent, nuclear genome reduction. In other words, the propensity for nuclear gene loss led to the retention of red algal plastid genes that would otherwise have undergone intracellular gene transfer to the nucleus. This hypothesis recognizes the primacy of nuclear genome evolution over that of plastids, which have no inherent control of their gene inventory and can change dramatically (e.g., secondarily non-photosynthetic eukaryotes, dinoflagellates) in response to selection acting on the host lineage. © 2017 Phycological Society of America.
Geographic patterns of genetic variation in native pecans
USDA-ARS?s Scientific Manuscript database
A structured collection of eighty seedling pecan trees [Carya illinoinensis (Wangenh.) K. Koch] representing nineteen putatively native pecan populations across the species range were evaluated at three plastid and 14 nuclear microsatellite (simple sequence repeat, SSR) loci. Data were analyzed usi...
Mouse cloning using a drop of peripheral blood.
Kamimura, Satoshi; Inoue, Kimiko; Ogonuki, Narumi; Hirose, Michiko; Oikawa, Mami; Yo, Masahiro; Ohara, Osamu; Miyoshi, Hiroyuki; Ogura, Atsuo
2013-08-01
Somatic cell nuclear transfer (SCNT) is a unique technology that produces cloned animals from single cells. It is desirable from a practical viewpoint that donor cells can be collected noninvasively and used readily for nuclear transfer. The present study was undertaken to determine whether peripheral blood cells freshly collected from living mice could be used for SCNT. We collected a drop of peripheral blood (15-45 μl) from the tail of a donor. A nucleated cell (leukocyte) suspension was prepared by lysing the red blood cells. Following SCNT using randomly selected leukocyte nuclei, cloned offspring were born at a 2.8% birth rate. Fluorescence-activated cell sorting revealed that granulocytes/monocytes and lymphocytes could be roughly distinguished by their sizes, the former being significantly larger. We then cloned putative granulocytes/monocytes and lymphocytes separately and obtained 2.1% and 1.7% birth rates, respectively (P > 0.05). Because the use of lymphocyte nuclei inevitably results in the birth of offspring with DNA rearrangements, we applied granulocyte/monocyte cloning to two genetically modified strains and two recombinant inbred strains. Normal-looking offspring were obtained from all four strains tested. The present study clearly indicated that genetic copies of mice could be produced using a drop of peripheral blood from living donors. This strategy will be applied to the rescue of infertile founder animals or a "last-of-line" animal possessing invaluable genetic resources.
2012-08-14
Defining the molecular and biochemical pathways re- sponsible for cell death phenotypes is essential for iden- tifying critical points that could be...clearly image nuclear structure resulted in PI-positive nuclei developing an orange hue. (B) Planimetric quantitation of nuclear size measured...metabolites on undifferentiated PC12 cells: a putative structure -toxicity relationship. Chem Res Toxicol 2006, 19(10):1294–1304. 10. McNutt P, Celver J
DOE Office of Scientific and Technical Information (OSTI.GOV)
Watson, M.; Yamamura, H.I.; Roeske, W.R.
The binding and regulation of selected muscarinic agonists to putative subtypes in rat cerebral cortex and heart were studied. Parallel inhibition studies of (/sup 3/H)pirenzepine ((/sup 3/H)PZ) and (-)-(/sup 3/H)quinuclidinylbenzilate ((-)-(/sup 3/H)QNB)-labeled membranes were done with and without 30 microM guanyl-5'-yl imidodiphosphate (Gpp(NH)p) at 25 degrees C in 10 mM Na-K-phosphate buffer which enhances PZ binding affinity and in modified Krebs-phosphate buffer, which mimics physiological conditions. Classical agonists such as carbachol, oxotremorine and acetylcholine inhibited (-)-(/sup 3/H)QNB binding to membranes with shallow Hill values (nH less than 1), were better fit to a 2-state model, were Gpp(NH)p-regulated and showed lowermore » affinity in modified Krebs-phosphate buffer than in 10 mM Na-K-phosphate buffer. Some agonists were not significantly better fit to a 2-state model in (/sup 3/H)PZ-labeled cortical membranes, especially in 10 mM Na-K-phosphate buffer. Whereas putative M1 and M2 binding sites distinguished by PZ possessed multiple agonist affinity states, as judged by carbachol, and agonist binding to (/sup 3/H)PZ-labeled sites were Gpp(NH)p modulated, the partial agonist pilocarpine and nonclassical agonist McN-A-343 (3-(m-chlorophenylcarbamoyloxy)-2-butynyl trimethylammonium chloride) showed little Gpp(NH)p-induced shift in (/sup 3/H)PZ-labeled cortical membranes in physiological conditions. Agonist binding to (-)-(/sup 3/H)QNB-labeled putative M2 cardiac sites was more sensitive to Gpp(NH)p than (-)-(/sup 3/H)QNB-labeled cortical sites. Carbachol and acetylcholine showed significant selectivity for putative M2 sites.« less
Molecular Evidence for Natural Hybridization between Cotoneaster dielsianus and C. glaucophyllus
Li, Mingwan; Chen, Sufang; Zhou, Renchao; Fan, Qiang; Li, Feifei; Liao, Wenbo
2017-01-01
Hybridization accompanied by polyploidization and apomixis has been demonstrated as a driving force in the evolution and speciation of many plants. A good example to study the evolutionary process of hybridization associated with polyploidy and apomixis is the genus Cotoneaster (Rosaceae), which includes approximately 150 species, most of which are polyploid apomicts. In this study, we investigated all Cotoneaster taxa distributed in a small region of Malipo, Yunnan, China. Based on the morphological characteristics, four Cotoneaster taxa were identified and sampled: C. dielsianus, C. glaucophyllus, C. franchetii, and a putative hybrid. Flow cytometry analyses showed that C. glaucophyllus was diploid, while the other three taxa were tetraploid. A total of five low-copy nuclear genes and six chloroplast regions were sequenced to validate the status of the putative hybrid. Sequence analyses showed that C. dielsianus and C. glaucophyllus are distantly related and they could be well separated using totally 50 fixed nucleotide substitutions and four fixed indels at the 11 investigated genes. All individuals of the putative hybrid harbored identical sequences: they showed chromatogram additivity for all fixed differences between C. dielsianus and C. glaucophyllus at the five nuclear genes, and were identical with C. glaucophyllus at the six chloroplast regions. Haplotype analysis revealed that C. dielsianus possessed nine haplotypes for the 11 genes, while C. glaucophyllus had ten, and there were no shared haplotypes between the two species. The putative hybrid harbored two haplotypes for each nuclear gene: one shared with C. dielsianus and the other with C. glaucophyllus. They possessed the same chloroplast haplotype with C. glaucophyllus. Our study provided convincing evidence for natural hybridization between C. dielsianus and C. glaucophyllus, and revealed that all hybrid individuals were derivatives of one initial F1 via apomixes. C. glaucophyllus served as the maternal parent at the initial hybridization event. We proposed that anthropological disturbance provided an opportunity for hybridization between C. dielsianus and C. glaucophyllus, and a tetraploid F1 successfully bred many identical progenies via apomixis. Under this situation, species integrity could be maintained for these Cotoneaster species, but attentions should be kept for this new-born hybrid. PMID:28536587
Federal Register 2010, 2011, 2012, 2013, 2014
2013-11-25
... industry guidance contained in Nuclear Energy Institute (NEI) 13-02, ``Industry Guidance for Compliance.... ML13295A225), and Nuclear Energy Institute by letter dated October 18, 2013 (ADAMS Accession No. ML13295A494... NUCLEAR REGULATORY COMMISSION [NRC-2013-0215] Compliance With Order EA-13-109, Order Modifying...
Wallace, Lisa E.; Culley, Theresa M.; Weller, Stephen G.; Sakai, Ann K.; Kuenzi, Ashley; Roy, Tilottama; Wagner, Warren L.; Nepokroeff, Molly
2011-01-01
Asymmetrical gene flow, which has frequently been documented in naturally occurring hybrid zones, can result from various genetic and demographic factors. Understanding these factors is important for determining the ecological conditions that permitted hybridization and the evolutionary potential inherent in hybrids. Here, we characterized morphological, nuclear, and chloroplast variation in a putative hybrid zone between Schiedea menziesii and S. salicaria, endemic Hawaiian species with contrasting breeding systems. Schiedea menziesii is hermaphroditic with moderate selfing; S. salicaria is gynodioecious and wind-pollinated, with partially selfing hermaphrodites and largely outcrossed females. We tested three hypotheses: 1) putative hybrids were derived from natural crosses between S. menziesii and S. salicaria, 2) gene flow via pollen is unidirectional from S. salicaria to S. menziesii and 3) in the hybrid zone, traits associated with wind pollination would be favored as a result of pollen-swamping by S. salicaria. Schiedea menziesii and S. salicaria have distinct morphologies and chloroplast genomes but are less differentiated at the nuclear loci. Hybrids are most similar to S. menziesii at chloroplast loci, exhibit nuclear allele frequencies in common with both parental species, and resemble S. salicaria in pollen production and pollen size, traits important to wind pollination. Additionally, unlike S. menziesii, the hybrid zone contains many females, suggesting that the nuclear gene responsible for male sterility in S. salicaria has been transferred to hybrid plants. Continued selection of nuclear genes in the hybrid zone may result in a population that resembles S. salicaria, but retains chloroplast lineage(s) of S. menziesii. PMID:21949765
Dworschak, Wolfgang; Ratz, Christoph; Wagner, Michael
2016-11-01
Numerous studies have reported a high prevalence of challenging behavior among students with intellectual disabilities (ID). They discuss different putative risk markers as well as their influence on the occurrence of challenging behavior. The study investigates the prevalence of challenging behavior and evaluates in terms of a replication study well-known putative risk markers among a representative sample of students with ID (N=1629) in Bavaria, one of the largest regions in Germany. The research is based on a modified version of the Developmental Behavior Checklist (DBC). Findings indicate a prevalence rate of 52% for challenging behavior. The following putative risk markers are associated with challenging behavior: intense need for care, male gender, lack of communication skills, and residential setting. These risk markers explain 8.4% of the variance concerning challenging behavior. These results reveal that challenging behavior either is to a large extent determined by situations and interactions between individuals and environment and cannot be explained by the measured individual and social risk markers alone, or it is determined by further risk markers that were not measured. Copyright © 2016 Elsevier Ltd. All rights reserved.
Paracchini, Valentina; Petrillo, Mauro; Reiting, Ralf; Angers-Loustau, Alexandre; Wahler, Daniela; Stolz, Andrea; Schönig, Birgit; Matthies, Anastasia; Bendiek, Joachim; Meinel, Dominik M; Pecoraro, Sven; Busch, Ulrich; Patak, Alex; Kreysa, Joachim; Grohmann, Lutz
2017-09-01
Many food and feed additives result from fermentation of genetically modified (GM) microorganisms. For vitamin B2 (riboflavin), GM Bacillus subtilis production strains have been developed and are often used. The presence of neither the GM strain nor its recombinant DNA is allowed for fermentation products placed on the EU market as food or feed additive. A vitamin B 2 product (80% feed grade) imported from China was analysed. Viable B. subtilis cells were identified and DNAs of two bacterial isolates (LHL and LGL) were subjected to three whole genome sequencing (WGS) runs with different devices (MiSeq, 454 or HiSeq system). WGS data revealed the integration of a chloramphenicol resistance gene, the deletion of the endogenous riboflavin (rib) operon and presence of four putative plasmids harbouring rib operons. Event- and construct-specific real-time PCR methods for detection of the GM strain and its putative plasmids in food and feed products have been developed. Copyright © 2017 Elsevier Ltd. All rights reserved.
Ali, Shawkat; Magne, Maxime; Chen, Shiyan; Côté, Olivier; Stare, Barbara Gerič; Obradovic, Natasa; Jamshaid, Lubna; Wang, Xiaohong; Bélair, Guy; Moffett, Peter
2015-01-01
The potato cyst nematode, Globodera rostochiensis, is an important pest of potato. Like other pathogens, plant parasitic nematodes are presumed to employ effector proteins, secreted into the apoplast as well as the host cytoplasm, to alter plant cellular functions and successfully infect their hosts. We have generated a library of ORFs encoding putative G. rostochiensis putative apoplastic effectors in vectors for expression in planta. These clones were assessed for morphological and developmental effects on plants as well as their ability to induce or suppress plant defenses. Several CLAVATA3/ESR-like proteins induced developmental phenotypes, whereas predicted cell wall-modifying proteins induced necrosis and chlorosis, consistent with roles in cell fate alteration and tissue invasion, respectively. When directed to the apoplast with a signal peptide, two effectors, an ubiquitin extension protein (GrUBCEP12) and an expansin-like protein (GrEXPB2), suppressed defense responses including NB-LRR signaling induced in the cytoplasm. GrEXPB2 also elicited defense response in species- and sequence-specific manner. Our results are consistent with the scenario whereby potato cyst nematodes secrete effectors that modulate host cell fate and metabolism as well as modifying host cell walls. Furthermore, we show a novel role for an apoplastic expansin-like protein in suppressing intra-cellular defense responses. PMID:25606855
Ali, Shawkat; Magne, Maxime; Chen, Shiyan; Côté, Olivier; Stare, Barbara Gerič; Obradovic, Natasa; Jamshaid, Lubna; Wang, Xiaohong; Bélair, Guy; Moffett, Peter
2015-01-01
The potato cyst nematode, Globodera rostochiensis, is an important pest of potato. Like other pathogens, plant parasitic nematodes are presumed to employ effector proteins, secreted into the apoplast as well as the host cytoplasm, to alter plant cellular functions and successfully infect their hosts. We have generated a library of ORFs encoding putative G. rostochiensis putative apoplastic effectors in vectors for expression in planta. These clones were assessed for morphological and developmental effects on plants as well as their ability to induce or suppress plant defenses. Several CLAVATA3/ESR-like proteins induced developmental phenotypes, whereas predicted cell wall-modifying proteins induced necrosis and chlorosis, consistent with roles in cell fate alteration and tissue invasion, respectively. When directed to the apoplast with a signal peptide, two effectors, an ubiquitin extension protein (GrUBCEP12) and an expansin-like protein (GrEXPB2), suppressed defense responses including NB-LRR signaling induced in the cytoplasm. GrEXPB2 also elicited defense response in species- and sequence-specific manner. Our results are consistent with the scenario whereby potato cyst nematodes secrete effectors that modulate host cell fate and metabolism as well as modifying host cell walls. Furthermore, we show a novel role for an apoplastic expansin-like protein in suppressing intra-cellular defense responses.
Honda, Akinobu; Chigwechokha, Petros Kingstone; Kamada-Futagami, Yuko; Komatsu, Masaharu; Shiozaki, Kazuhiro
2018-06-01
Sialidase catalyzes the removal of sialic acids from glycoconjugates. Different from Neu1 and Neu3 sialidases, Neu4 enzymatic properties such as substrate specificity and subcellular localization are not well-conserved among vertebrates. In fish only zebrafish and medaka neu4 genes have been cloned and their polypeptides have been characterized so far. Thus, characterization of Neu4 from other fish species is necessary to evaluate Neu4 physiological functions. Here, Nile tilapia was chosen for the characterization of Neu4 polypeptide considering that it is one of the major cultured fish all over the world and that its genomic sequences are now available. Coding DNA sequence of tilapia Neu4 was identified as 1,497 bp and its recombinant protein showed broad substrate specificity and optimal sialidase enzyme activity pH at 4.0. Neu4 activity was sustained even in neutral and alkali pH. Interestingly, immunofluorescence analysis revealed that major subcellular localization of tilapia Neu4 was nuclear, quite distinct from zebrafish (ER) and medaka Neu4 (lysosome). Bioinformatic analysis showed the existence of putative nuclear localization signal (NLS) in tilapia Neu4. In general, it is known that importin families bind to several proteins via NLS and transfer them into nucleus. Therefore, to determine the involvement of putative NLS in Neu4 nuclear localization, Neu4 mutant deleting NLS was constructed and expressed in cultured cells. As a result, NLS deletion significantly diminished the nuclear localization. Furthermore, treatment of importazole, interrupter of binding importin β and RanGTP, significantly suppressed Neu4 nuclear localization. In summary, tilapia Neu4 is a unique sialidase localized at nucleus and its transport system into nucleus is regulated by importin. Copyright © 2018 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.
Swathy, Babu; Banerjee, Moinak
2017-01-01
Haloperidol has been extensively used in various psychiatric conditions. It has also been reported to induce severe side effects. We aimed to evaluate whether haloperidol can influence host methylome, and if so what are the possible mechanisms for it in neuronal cells. Impact on host methylome and miRNAs can have wide spread alterations in gene expression, which might possibly help in understanding how haloperidol may impact treatment response or induce side effects. SK-N-SH, a neuroblasoma cell line was treated with haloperidol at 10μm concentration for 24 hours and global DNA methylation was evaluated. Methylation at global level is maintained by methylation maintenance machinery and certain miRNAs. Therefore, the expression of methylation maintenance genes and their putative miRNA expression profiles were assessed. These global methylation alterations could result in gene expression changes. Therefore genes expressions for neurotransmitter receptors, regulators, ion channels and transporters were determined. Subsequently, we were also keen to identify a strong candidate miRNA based on biological and in-silico approach which can reflect on the pharmacoepigenetic trait of haloperidol and can also target the altered neuroscience panel of genes used in the study. Haloperidol induced increase in global DNA methylation which was found to be associated with corresponding increase in expression of various epigenetic modifiers that include DNMT1, DNMT3A, DNMT3B and MBD2. The expression of miR-29b that is known to putatively regulate the global methylation by modulating the expression of epigenetic modifiers was observed to be down regulated by haloperidol. In addition to miR-29b, miR-22 was also found to be downregulated by haloperidol treatment. Both these miRNA are known to putatively target several genes associated with various epigenetic modifiers, pharmacogenes and neurotransmission. Interestingly some of these putative target genes involved in neurotransmission were observed to be upregulated while CHRM2 gene expression was down regulated. Haloperidol can influence methylation traits thereby inducing a pharmacoepigenomic response, which seems to be regulated by DNMTs and their putative miRNA expression. Increased methylation seems to influence CHRM2 gene expression while microRNA could influence neurotransmission, pharmacogene expression and methylation events. Altered expression of various therapeutically relevant genes and miRNA expression, could account for their role in therapeutic response or side effects.
Swathy, Babu
2017-01-01
Introduction Haloperidol has been extensively used in various psychiatric conditions. It has also been reported to induce severe side effects. We aimed to evaluate whether haloperidol can influence host methylome, and if so what are the possible mechanisms for it in neuronal cells. Impact on host methylome and miRNAs can have wide spread alterations in gene expression, which might possibly help in understanding how haloperidol may impact treatment response or induce side effects. Methods SK-N-SH, a neuroblasoma cell line was treated with haloperidol at 10μm concentration for 24 hours and global DNA methylation was evaluated. Methylation at global level is maintained by methylation maintenance machinery and certain miRNAs. Therefore, the expression of methylation maintenance genes and their putative miRNA expression profiles were assessed. These global methylation alterations could result in gene expression changes. Therefore genes expressions for neurotransmitter receptors, regulators, ion channels and transporters were determined. Subsequently, we were also keen to identify a strong candidate miRNA based on biological and in-silico approach which can reflect on the pharmacoepigenetic trait of haloperidol and can also target the altered neuroscience panel of genes used in the study. Results Haloperidol induced increase in global DNA methylation which was found to be associated with corresponding increase in expression of various epigenetic modifiers that include DNMT1, DNMT3A, DNMT3B and MBD2. The expression of miR-29b that is known to putatively regulate the global methylation by modulating the expression of epigenetic modifiers was observed to be down regulated by haloperidol. In addition to miR-29b, miR-22 was also found to be downregulated by haloperidol treatment. Both these miRNA are known to putatively target several genes associated with various epigenetic modifiers, pharmacogenes and neurotransmission. Interestingly some of these putative target genes involved in neurotransmission were observed to be upregulated while CHRM2 gene expression was down regulated. Conclusions Haloperidol can influence methylation traits thereby inducing a pharmacoepigenomic response, which seems to be regulated by DNMTs and their putative miRNA expression. Increased methylation seems to influence CHRM2 gene expression while microRNA could influence neurotransmission, pharmacogene expression and methylation events. Altered expression of various therapeutically relevant genes and miRNA expression, could account for their role in therapeutic response or side effects. PMID:28886082
2010-01-01
Background The agriculturally important pasture grass tall fescue (Festuca arundinacea Schreb. syn. Lolium arundinaceum (Schreb.) Darbysh.) is an outbreeding allohexaploid, that may be more accurately described as a species complex consisting of three major (Continental, Mediterranean and rhizomatous) morphotypes. Observation of hybrid infertility in some crossing combinations between morphotypes suggests the possibility of independent origins from different diploid progenitors. This study aims to clarify the evolutionary relationships between each tall fescue morphotype through phylogenetic analysis using two low-copy nuclear genes (encoding plastid acetyl-CoA carboxylase [Acc1] and centroradialis [CEN]), the nuclear ribosomal DNA internal transcribed spacer (rDNA ITS) and the chloroplast DNA (cpDNA) genome-located matK gene. Other taxa within the closely related Lolium-Festuca species complex were also included in the study, to increase understanding of evolutionary processes in a taxonomic group characterised by multiple inter-specific hybridisation events. Results Putative homoeologous sequences from both nuclear genes were obtained from each polyploid species and compared to counterparts from 15 diploid taxa. Phylogenetic reconstruction confirmed F. pratensis and F. arundinacea var. glaucescens as probable progenitors to Continental tall fescue, and these species are also likely to be ancestral to the rhizomatous morphotype. However, these two morphotypes are sufficiently distinct to be located in separate clades based on the ITS-derived data set. All four of the generated data sets suggest independent evolution of the Mediterranean and Continental morphotypes, with minimal affinity between cognate sequence haplotypes. No obvious candidate progenitor species for Mediterranean tall fescues were identified, and only two putative sub-genome-specific haplotypes were identified for this morphotype. Conclusions This study describes the first phylogenetic analysis of the Festuca genus to include representatives of each tall fescue morphotype, and to use low copy nuclear gene-derived sequences to identify putative progenitors of the polyploid species. The demonstration of distinct tall fescue lineages has implications for both taxonomy and molecular breeding strategies, and may facilitate the generation of morphotype and/or sub-genome-specific molecular markers. PMID:20937141
Wiermer, Marcel; Cheng, Yu Ti; Imkampe, Julia; Li, Meilan; Wang, Dongmei; Lipka, Volker; Li, Xin
2012-06-01
In eukaryotic cells, transduction of external stimuli into the nucleus to induce transcription and export of mRNAs for translation in the cytoplasm is mediated by nuclear pore complexes (NPCs) composed of nucleoporin proteins (Nups). We previously reported that Arabidopsis MOS3, encoding the homolog of vertebrate Nup96, is required for plant immunity and constitutive resistance mediated by the de-regulated Toll interleukin 1 receptor/nucleotide-binding/leucine-rich repeat (TNL)-type R gene snc1. In vertebrates, Nup96 is a component of the conserved Nup107-160 nuclear pore sub-complex, and implicated in immunity-related mRNA export. Here, we used a reverse genetics approach to examine the requirement for additional subunits of the predicted Arabidopsis Nup107-160 complex in plant immunity. We show that, among eight putative complex members, beside MOS3, only plants with defects in Nup160 or Seh1 are impaired in basal resistance. Constitutive resistance in the snc1 mutant and immunity mediated by TNL-type R genes also depend on functional Nup160 and have a partial requirement for Seh1. Conversely, resistance conferred by coiled coil-type immune receptors operates largely independently of both genes, demonstrating specific contributions to plant defense signaling. Our functional analysis further revealed that defects in nup160 and seh1 result in nuclear accumulation of poly(A) mRNA, and, in the case of nup160, considerable depletion of EDS1, a key positive regulator of basal and TNL-triggered resistance. These findings suggest that Nup160 is required for nuclear mRNA export and full expression of EDS1-conditioned resistance pathways in Arabidopsis. © 2012 The Authors. The Plant Journal © 2012 Blackwell Publishing Ltd.
Zhang, Jin-Ju; Montgomery, Benjamin R.; Huang, Shuang-Quan
2016-01-01
Interspecific hybridization is widespread among plants; nevertheless, pre- and post-zygotic isolating mechanisms may maintain species integrity for interfertile species in sympatry despite some gene flow. Interspecific hybridization and potential isolating barriers were evaluated between co-flowering Silene asclepiadea and Silene yunnanensis in an alpine community in southwest China. We investigated morphological and molecular (nuclear microsatellites and chloroplast gene sequence) variation in sympatric populations of S. asclepiadea and S. yunnanensis. Additionally, we analyzed pollinator behaviour and compared reproductive success between the putative hybrids and their parental species. Both the molecular and morphological data indicate that there were putative natural hybrids in the field, with S. asclepiadae the ovule parent and S. yunnanensis the pollen parent. Bumblebees were the primary visitors to S. asclepiadae and putative hybrids, while butterflies were the primary visitors to S. yunnanensis. Pollen production and viability were significantly lower in putative hybrids than the parental species. The direction of hybridization is quite asymmetric from S. yunnanensis to S. asclepiadea. Protandry combined with later peak flowering of S. yunnanensis, and pollinator preference may have contributed to the asymmetric pattern of hybridization, but putative hybrids were rare. Our results thus suggest that despite gene flow, S. asclepiadea and S. yunnanensis can maintain species boundaries, perhaps as a result of floral isolation and low fecundity of the hybrids. PMID:27178066
Zhang, Jin-Ju; Montgomery, Benjamin R; Huang, Shuang-Quan
2016-01-01
Interspecific hybridization is widespread among plants; nevertheless, pre- and post-zygotic isolating mechanisms may maintain species integrity for interfertile species in sympatry despite some gene flow. Interspecific hybridization and potential isolating barriers were evaluated between co-flowering Silene asclepiadea and Silene yunnanensis in an alpine community in southwest China. We investigated morphological and molecular (nuclear microsatellites and chloroplast gene sequence) variation in sympatric populations of S. asclepiadea and S. yunnanensis. Additionally, we analyzed pollinator behaviour and compared reproductive success between the putative hybrids and their parental species. Both the molecular and morphological data indicate that there were putative natural hybrids in the field, with S. asclepiadae the ovule parent and S. yunnanensis the pollen parent. Bumblebees were the primary visitors to S. asclepiadae and putative hybrids, while butterflies were the primary visitors to S. yunnanensis Pollen production and viability were significantly lower in putative hybrids than the parental species. The direction of hybridization is quite asymmetric from S. yunnanensis to S. asclepiadea Protandry combined with later peak flowering of S. yunnanensis, and pollinator preference may have contributed to the asymmetric pattern of hybridization, but putative hybrids were rare. Our results thus suggest that despite gene flow, S. asclepiadea and S. yunnanensis can maintain species boundaries, perhaps as a result of floral isolation and low fecundity of the hybrids. Published by Oxford University Press on behalf of the Annals of Botany Company.
Kamita, S G; Maeda, S
1993-01-01
Coinfection of Bombyx mori nuclear polyhedrosis virus (BmNPV) with Autographa californica NPV (AcNPV) in the BmNPV-permissive BmN cell line resulted in the complete inhibition of BmNPV replication. Coinfected BmN cells exhibited an atypical cytopathic effect (CPE) and synthesis of viral and host proteins was dramatically attenuated by 5 h postinfection (p.i.) and nearly completely blocked by 24 h p.i. Viral transcription, however, appeared to occur normally during both early (5-h-p.i.) and late (24-h-p.i.) stages of infection. Superinfection of BmN cells with AcNPV at 5 and 12 h post-BmNPV infection resulted in limited inhibition of BmNPV replication. BmN cells singly infected with AcNPV also showed similar CPE, premature inhibition of viral and host protein synthesis, and apparently normal viral transcription. BmNPV replication occurred normally following coinfection of BmNPV and eh2-AcNPV, an AcNPV mutant identical to AcNPV except for a 572-bp region in its putative DNA helicase gene originating from BmNPV (S. Maeda, S. G. Kamita, and A. Kondo, J. Virol. 67:6234-6238, 1993). Furthermore, atypical CPE and premature attenuation of host and viral protein synthesis were not observed. These results indicated that the inhibition of BmNPV replication was caused either directly or indirectly at the translational level by the putative AcNPV DNA helicase gene. Images PMID:7690422
USDA-ARS?s Scientific Manuscript database
Nematodes within the Xiphinema americanum species complex are economically important because they vector nepoviruses which cause considerable damage to a variety of agricultural crops. The taxonomy of X. americanum is controversial, with the number of putative species being the subject of debate. Ac...
USDA-ARS?s Scientific Manuscript database
The phylogeny of Amaryllidaceae tribe Hippeastreae was inferred using chloroplast (3’ycf1, ndhF, trnL-F) and nuclear (ITS rDNA) sequence data under maximum parsimony and maximum likelihood frameworks. Network analyses were applied to resolve conflicting signals among data sets and putative scenarios...
Wragg, Peter D; Johnson, Steven D
2011-09-01
Transitions from wind pollination to insect pollination were pivotal to the radiation of land plants, yet only a handful are known and the trait shifts required are poorly understood. We tested the hypothesis that a transition to insect pollination took place in the ancestrally wind-pollinated sedges (Cyperaceae) and that floral traits modified during this transition have functional significance. We paired putatively insect-pollinated Cyperus obtusiflorus and Cyperus sphaerocephalus with related, co-flowering, co-occurring wind-pollinated species, and compared pairs in terms of pollination mode and functional roles of floral traits. Experimentally excluding insects reduced seed set by 56-89% in putatively insect-pollinated species but not in intermingled wind-pollinated species. The pollen of putatively insect-pollinated species was less motile in a wind tunnel than that of wind-pollinated species. Bees, beetles and flies preferred inflorescences, and color-matched white or yellow models, of putatively insect-pollinated species over inflorescences, or color-matched brown models, of wind-pollinated species. Floral scents of putatively insect-pollinated species were chemically consistent with those of other insect-pollinated plants, and attracted pollinators; wind-pollinated species were unscented. These results show that a transition from wind pollination to insect pollination occurred in sedges and shed new light on the function of traits involved in this important transition. © 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.
Syn, Genevieve; Blackwell, Jenefer M; Jamieson, Sarra E; Francis, Richard W
2018-01-01
Toxoplasma gondii uses epigenetic mechanisms to regulate both endogenous and host cell gene expression. To identify genes with putative epigenetic functions, we developed an in silico pipeline to interrogate the T. gondii proteome of 8313 proteins. Step 1 employs PredictNLS and NucPred to identify genes predicted to target eukaryotic nuclei. Step 2 uses GOLink to identify proteins of epigenetic function based on Gene Ontology terms. This resulted in 611 putative nuclear localised proteins with predicted epigenetic functions. Step 3 filtered for secretory proteins using SignalP, SecretomeP, and experimental data. This identified 57 of the 611 putative epigenetic proteins as likely to be secreted. The pipeline is freely available online, uses open access tools and software with user-friendly Perl scripts to automate and manage the results, and is readily adaptable to undertake any such in silico search for genes contributing to particular functions.
Identification of novel nuclear localization signals of Drosophila myeloid leukemia factor.
Sugano, Wakana; Yamaguchi, Masamitsu
2007-01-01
Myeloid leukemia factor 1 (MLF1) was first identified as part of a leukemic fusion protein produced by a chromosomal translocation, and MLF family proteins are present in many animals. In mammalian cells, MLF1 has been described as mainly cytoplasmic, but in Drosophila, one of the dMLF isoforms (dMLFA) localized mainly in the nucleus while the other isoform (dMLFB), that appears to be produced by the alternative splicing, displays both nuclear and cytoplasmic localization. To investigate the difference in subcellular localization between MLF family members, we examined the subcellular localization of deletion mutants of dMLFA isoform. The analyses showed that the C-terminal 40 amino acid region of dMLFA is necessary and sufficient for nuclear localization. Based on amino acid sequences, we hypothesized that two nuclear localization signals (NLSs) are present within the region. Site-directed mutagenesis of critical residues within the two putative NLSs leads to loss of nuclear localization, suggesting that both NLS motifs are necessary for nuclear localization.
Jia, Haiwei; Zhang, Xiaojuan; Wang, Wenjun; Bai, Yuanyuan; Ling, Youguo; Cao, Cheng; Ma, Runlin Z; Zhong, Hui; Wang, Xue; Xu, Quanbin
2015-02-27
Mps1, an essential component of the mitotic checkpoint, is also an important interphase regulator and has roles in DNA damage response, cytokinesis and centrosome duplication. Mps1 predominantly resides in the cytoplasm and relocates into the nucleus at the late G2 phase. So far, the mechanism underlying the Mps1 translocation between the cytoplasm and nucleus has been unclear. In this work, a dynamic export process of Mps1 from the nucleus to cytoplasm in interphase was revealed- a process blocked by the Crm1 inhibitor, Leptomycin B, suggesting that export of Mps1 is Crm1 dependent. Consistent with this speculation, a direct association between Mps1 and Crm1 was found. Furthermore, a putative nuclear export sequence (pNES) motif at the N-terminal of Mps1 was identified by analyzing the motif of Mps1. This motif shows a high sequence similarity to the classic NES, a fusion of this motif with EGFP results in dramatic exclusion of the fusion protein from the nucleus. Additionally, Mps1 mutant loss of pNES integrity was shown by replacing leucine with alanine which produced a diffused subcellular distribution, compared to the wild type protein which resides predominantly in cytoplasm. Taken these findings together, it was concluded that the pNES sequence is sufficient for the Mps1 export from nucleus during interphase.
USDA-ARS?s Scientific Manuscript database
The use of genetically modified bacteria to deliver biologically active molecules directly to the gut has become an increasingly attractive area of investigation. The challenge of regulation of production of the therapeutic molecule and colonization of the bowel led us to investigate Bacteroides ov...
The Use of Basalt, Basalt Fibers and Modified Graphite for Nuclear Waste Repository - 12150
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gulik, V.I.; Biland, A.B.
2012-07-01
New materials enhancing the isolation of radioactive waste and spent nuclear fuel are continuously being developed.. Our research suggests that basalt-based materials, including basalt roving chopped basalt fiber strands, basalt composite rebar and materials based on modified graphite, could be used for enhancing radioactive waste isolation during the storage and disposal phases and maintaining it during a significant portion of the post-closure phase. The basalt vitrification process of nuclear waste is a viable alternative to glass vitrification. Basalt roving, chopped basalt fiber strands and basalt composite rebars can significantly increase the strength and safety characteristics of nuclear waste and spentmore » nuclear fuel storages. Materials based on MG are optimal waterproofing materials for nuclear waste containers. (authors)« less
Faheem, Muhammad; Martins-de-Sa, Diogo; Vidal, Julia F D; Álvares, Alice C M; Brandão-Neto, José; Bird, Louise E; Tully, Mark D; von Delft, Frank; Souto, Betulia M; Quirino, Betania F; Freitas, Sonia M; Barbosa, João Alexandre R G
2016-12-09
A current metagenomics focus is to interpret and transform collected genomic data into biological information. By combining structural, functional and genomic data we have assessed a novel bacterial protein selected from a carbohydrate-related activity screen in a microbial metagenomic library from Capra hircus (domestic goat) gut. This uncharacterized protein was predicted as a bacterial cell wall-modifying enzyme (CWME) and shown to contain four domains: an N-terminal, a cysteine protease, a peptidoglycan-binding and an SH3 bacterial domain. We successfully cloned, expressed and purified this putative cysteine protease (PCP), which presented autoproteolytic activity and inhibition by protease inhibitors. We observed cell wall hydrolytic activity and ampicillin binding capacity, a characteristic of most bacterial CWME. Fluorimetric binding analysis yielded a K b of 1.8 × 10 5 M -1 for ampicillin. Small-angle X-ray scattering (SAXS) showed a maximum particle dimension of 95 Å with a real-space R g of 28.35 Å. The elongated molecular envelope corroborates the dynamic light scattering (DLS) estimated size. Furthermore, homology modeling and SAXS allowed the construction of a model that explains the stability and secondary structural changes observed by circular dichroism (CD). In short, we report a novel cell wall-modifying autoproteolytic PCP with insight into its biochemical, biophysical and structural features.
Torres-Cortés, Gloria; Ghignone, Stefano; Bonfante, Paola; Schüßler, Arthur
2015-06-23
For more than 450 million years, arbuscular mycorrhizal fungi (AMF) have formed intimate, mutualistic symbioses with the vast majority of land plants and are major drivers in almost all terrestrial ecosystems. The obligate plant-symbiotic AMF host additional symbionts, so-called Mollicutes-related endobacteria (MRE). To uncover putative functional roles of these widespread but yet enigmatic MRE, we sequenced the genome of DhMRE living in the AMF Dentiscutata heterogama. Multilocus phylogenetic analyses showed that MRE form a previously unidentified lineage sister to the hominis group of Mycoplasma species. DhMRE possesses a strongly reduced metabolic capacity with 55% of the proteins having unknown function, which reflects unique adaptations to an intracellular lifestyle. We found evidence for transkingdom gene transfer between MRE and their AMF host. At least 27 annotated DhMRE proteins show similarities to nuclear-encoded proteins of the AMF Rhizophagus irregularis, which itself lacks MRE. Nuclear-encoded homologs could moreover be identified for another AMF, Gigaspora margarita, and surprisingly, also the non-AMF Mortierella verticillata. Our data indicate a possible origin of the MRE-fungus association in ancestors of the Glomeromycota and Mucoromycotina. The DhMRE genome encodes an arsenal of putative regulatory proteins with eukaryotic-like domains, some of them encoded in putative genomic islands. MRE are highly interesting candidates to study the evolution and interactions between an ancient, obligate endosymbiotic prokaryote with its obligate plant-symbiotic fungal host. Our data moreover may be used for further targeted searches for ancient effector-like proteins that may be key components in the regulation of the arbuscular mycorrhiza symbiosis.
26 CFR 1.468A-4T - Treatment of nuclear decommissioning fund (temporary).
Code of Federal Regulations, 2010 CFR
2010-04-01
... 26 Internal Revenue 6 2010-04-01 2010-04-01 false Treatment of nuclear decommissioning fund...-4T Treatment of nuclear decommissioning fund (temporary). (a) In general. A nuclear decommissioning... income earned by the assets of the nuclear decommissioning fund. (b) Modified gross income. For purposes...
26 CFR 1.468A-4 - Treatment of nuclear decommissioning fund.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 26 Internal Revenue 6 2013-04-01 2013-04-01 false Treatment of nuclear decommissioning fund. 1...-4 Treatment of nuclear decommissioning fund. (a) In general. A nuclear decommissioning fund is... by the assets of the nuclear decommissioning fund. (b) Modified gross income. For purposes of this...
26 CFR 1.468A-4 - Treatment of nuclear decommissioning fund.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 26 Internal Revenue 6 2011-04-01 2011-04-01 false Treatment of nuclear decommissioning fund. 1...-4 Treatment of nuclear decommissioning fund. (a) In general. A nuclear decommissioning fund is... by the assets of the nuclear decommissioning fund. (b) Modified gross income. For purposes of this...
26 CFR 1.468A-4 - Treatment of nuclear decommissioning fund.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 26 Internal Revenue 6 2014-04-01 2014-04-01 false Treatment of nuclear decommissioning fund. 1...-4 Treatment of nuclear decommissioning fund. (a) In general. A nuclear decommissioning fund is... by the assets of the nuclear decommissioning fund. (b) Modified gross income. For purposes of this...
26 CFR 1.468A-4 - Treatment of nuclear decommissioning fund.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 26 Internal Revenue 6 2012-04-01 2012-04-01 false Treatment of nuclear decommissioning fund. 1...-4 Treatment of nuclear decommissioning fund. (a) In general. A nuclear decommissioning fund is... by the assets of the nuclear decommissioning fund. (b) Modified gross income. For purposes of this...
Adam, Rosalyn M; Yang, Wei; Di Vizio, Dolores; Mukhopadhyay, Nishit K; Steen, Hanno
2008-06-05
Cholesterol-rich membrane microdomains known as lipid rafts have been implicated in diverse physiologic processes including lipid transport and signal transduction. Lipid rafts were originally defined as detergent-resistant membranes (DRMs) due to their relative insolubility in cold non-ionic detergents. Recent findings suggest that, although DRMs are not equivalent to lipid rafts, the presence of a given protein within DRMs strongly suggests its potential for raft association in vivo. Therefore, isolation of DRMs represents a useful starting point for biochemical analysis of lipid rafts. The physicochemical properties of DRMs present unique challenges to analysis of their protein composition. Existing methods of isolating DRM-enriched fractions involve flotation of cell extracts in a sucrose density gradient, which, although successful, can be labor intensive, time consuming and results in dilute sucrose-containing fractions with limited utility for direct proteomic analysis. In addition, several studies describing the proteomic characterization of DRMs using this and other approaches have reported the presence of nuclear proteins in such fractions. It is unclear whether these results reflect trafficking of nuclear proteins to DRMs or whether they arise from nuclear contamination during isolation. To address these issues, we have modified a published differential detergent extraction method to enable rapid DRM isolation that minimizes nuclear contamination and yields fractions compatible with mass spectrometry. DRM-enriched fractions isolated using the conventional or modified extraction methods displayed comparable profiles of known DRM-associated proteins, including flotillins, GPI-anchored proteins and heterotrimeric G-protein subunits. Thus, the modified procedure yielded fractions consistent with those isolated by existing methods. However, we observed a marked reduction in the percentage of nuclear proteins identified in DRM fractions isolated with the modified method (15%) compared to DRMs isolated by conventional means (36%). Furthermore, of the 21 nuclear proteins identified exclusively in modified DRM fractions, 16 have been reported to exist in other subcellular sites, with evidence to suggest shuttling of these species between the nucleus and other organelles. We describe a modified DRM isolation procedure that generates DRMs that are largely free of nuclear contamination and that is compatible with downstream proteomic analyses with minimal additional processing. Our findings also imply that identification of nuclear proteins in DRMs is likely to reflect legitimate movement of proteins between compartments, and is not a result of contamination during extraction.
Chen, Changlong; Chen, Yongpan; Jian, Heng; Yang, Dan; Dai, Yiran; Pan, Lingling; Shi, Fengwei; Yang, Shanshan; Liu, Qian
2018-01-01
Heterodera avenae is one of the most important plant pathogens and causes vast losses in cereal crops. As a sedentary endoparasitic nematode, H. avenae secretes effectors that modify plant defenses and promote its biotrophic infection of its hosts. However, the number of effectors involved in the interaction between H. avenae and host defenses remains unclear. Here, we report the identification of putative effectors in H. avenae that regulate plant defenses on a large scale. Our results showed that 78 of the 95 putative effectors suppressed programmed cell death (PCD) triggered by BAX and that 7 of the putative effectors themselves caused cell death in Nicotiana benthamiana. Among the cell-death-inducing effectors, three were found to be dependent on their specific domains to trigger cell death and to be expressed in esophageal gland cells by in situ hybridization. Ten candidate effectors that suppressed BAX-triggered PCD also suppressed PCD triggered by the elicitor PsojNIP and at least one R-protein/cognate effector pair, suggesting that they are active in suppressing both pattern-triggered immunity (PTI) and effector-triggered immunity (ETI). Notably, with the exception of isotig16060, these putative effectors could also suppress PCD triggered by cell-death-inducing effectors from H. avenae, indicating that those effectors may cooperate to promote nematode parasitism. Collectively, our results indicate that the majority of the tested effectors of H. avenae may play important roles in suppressing cell death induced by different elicitors in N. benthamiana. PMID:29379510
The Oncogene PDRG1 Is an Interaction Target of Methionine Adenosyltransferases
Garrido, Francisco; Reytor, Edel; Portillo, Francisco; Pajares, María A.
2016-01-01
Methionine adenosyltransferases MAT I and MAT III (encoded by Mat1a) catalyze S-adenosylmethionine synthesis in normal liver. Major hepatic diseases concur with reduced levels of this essential methyl donor, which are primarily due to an expression switch from Mat1a towards Mat2a. Additional changes in the association state and even in subcellular localization of these isoenzymes are also detected. All these alterations result in a reduced content of the moderate (MAT I) and high Vmax (MAT III) isoenzymes, whereas the low Vmax (MAT II) isoenzyme increases and nuclear accumulation of MAT I is observed. These changes derive in a reduced availability of cytoplasmic S-adenosylmethionine, together with an effort to meet its needs in the nucleus of damaged cells, rendering enhanced levels of certain epigenetic modifications. In this context, the putative role of protein-protein interactions in the control of S-adenosylmethionine synthesis has been scarcely studied. Using yeast two hybrid and a rat liver library we identified PDRG1 as an interaction target for MATα1 (catalytic subunit of MAT I and MAT III), further confirmation being obtained by immunoprecipitation and pull-down assays. Nuclear MATα interacts physically and functionally with the PDRG1 oncogene, resulting in reduced DNA methylation levels. Increased Pdrg1 expression is detected in acute liver injury and hepatoma cells, together with decreased Mat1a expression and nuclear accumulation of MATα1. Silencing of Pdrg1 expression in hepatoma cells alters their steady-state expression profile on microarrays, downregulating genes associated with tumor progression according to GO pathway analysis. Altogether, the results unveil the role of PDRG1 in the control of the nuclear methylation status through methionine adenosyltransferase binding and its putative collaboration in the progression of hepatic diseases. PMID:27548429
Joint Estimation of Contamination, Error and Demography for Nuclear DNA from Ancient Humans
Slatkin, Montgomery
2016-01-01
When sequencing an ancient DNA sample from a hominin fossil, DNA from present-day humans involved in excavation and extraction will be sequenced along with the endogenous material. This type of contamination is problematic for downstream analyses as it will introduce a bias towards the population of the contaminating individual(s). Quantifying the extent of contamination is a crucial step as it allows researchers to account for possible biases that may arise in downstream genetic analyses. Here, we present an MCMC algorithm to co-estimate the contamination rate, sequencing error rate and demographic parameters—including drift times and admixture rates—for an ancient nuclear genome obtained from human remains, when the putative contaminating DNA comes from present-day humans. We assume we have a large panel representing the putative contaminant population (e.g. European, East Asian or African). The method is implemented in a C++ program called ‘Demographic Inference with Contamination and Error’ (DICE). We applied it to simulations and genome data from ancient Neanderthals and modern humans. With reasonable levels of genome sequence coverage (>3X), we find we can recover accurate estimates of all these parameters, even when the contamination rate is as high as 50%. PMID:27049965
Xie, Qi; Liu, Xue; Zhang, Yinbing; Tang, Jinfu; Yin, Dedong; Fan, Bo; Zhu, Lihuang; Han, Liebao; Song, Guilong; Li, Dayong
2017-01-01
Due to its high biomass yield, low environmental impact, and widespread adaptability to poor soils and harsh conditions, switchgrass ( Panicum virgatum L.), a warm-region perennial herbaceous plant, has attracted much attention in recent years. However, little is known about microRNAs (miRNAs) and their functions in this bioenergy grass. Here, we identified and characterized a miRNA gene, Pvi-MIR319a , encoding microRNA319a in switchgrass. Transgenic rice lines generated by overexpressing the Pvi-MIR319a precursor gene exhibited broader leaves and delayed flowering compared with the control. Gene expression analysis indicated at least four putative target genes were downregulated. Additionally, we cloned a putative target gene ( PvPCF5 ) of Pvi-MIR319a from switchgrass. PvPCF5, a TCP transcription factor, is a nuclear-localized protein with transactivation activity and control the development of leaf. Our results suggest that Pvi-MIR319a and its target genes may be used as potential genetic regulators for future switchgrass genetic improvement.
Are plant formins integral membrane proteins?
Cvrcková, F
2000-01-01
The formin family of proteins has been implicated in signaling pathways of cellular morphogenesis in both animals and fungi; in the latter case, at least, they participate in communication between the actin cytoskeleton and the cell surface. Nevertheless, they appear to be cytoplasmic or nuclear proteins, and it is not clear whether they communicate with the plasma membrane, and if so, how. Because nothing is known about formin function in plants, I performed a systematic search for putative Arabidopsis thaliana formin homologs. I found eight putative formin-coding genes in the publicly available part of the Arabidopsis genome sequence and analyzed their predicted protein sequences. Surprisingly, some of them lack parts of the conserved formin-homology 2 (FH2) domain and the majority of them seem to have signal sequences and putative transmembrane segments that are not found in yeast or animals formins. Plant formins define a distinct subfamily. The presence in most Arabidopsis formins of sequence motifs typical or transmembrane proteins suggests a mechanism of membrane attachment that may be specific to plant formins, and indicates an unexpected evolutionary flexibility of the conserved formin domain.
The radial distribution of supernovae in nuclear starbursts
NASA Astrophysics Data System (ADS)
Herrero-Illana, R.; Pérez-Torres, M. A.; Alberdi, A.
2013-05-01
Galaxy-galaxy interactions are expected to be responsible for triggering massive star formation and possibly accretion onto a supermassive black hole, by providing large amounts of dense molecular gas down to the central kiloparsec region. Several scenarios to drive the gas further down to the central ˜100 pc, have been proposed, including the formation of a nuclear disk around the black hole, where massive stars would produce supernovae. Here, we probe the radial distribution of supernovae and supernova remnants in the nuclear regions of the starburst galaxies M82, Arp 299-A, and Arp 220, by using high-angular resolution (≲ 0.''1) radio observations. We derived scale-length values for the putative nuclear disks, which range from ˜20-30 pc for Arp 299-A and Arp 220, up to ˜140 pc for M82. The radial distribution of SNe for the nuclear disks in Arp 299-A and Arp 220 is also consistent with a power-law surface density profile of exponent γ = 1, as expected from detailed hydrodynamical simulations of nuclear disks. This study is detailed in te{herrero-illana12}.
Roscoe, Eileen M.; Schlichenmeyer, Kevin J.; Dube, William V.
2015-01-01
When inconclusive functional analysis (FA) outcomes occur, a number of modifications have been made to enhance the putative establishing operation or consequence associated with behavioral maintenance. However, a systematic method for identifying relevant events to test during modified FAs has not been evaluated. The purpose of this study was to develop and evaluate a technology for systematically identifying events to test in a modified FA after an initial FA led to inconclusive outcomes. Six individuals whose initial FA showed little or no responding or high levels only in the control condition participated. An indirect assessment (IA) questionnaire developed for identifying idiosyncratic variables was administered, and a descriptive analysis (DA) was conducted. Results from the IA only or a combination of the IA and DA were used to inform modified FA test and control conditions. Conclusive FA outcomes were obtained with five of the six participants during the modified FA phase. PMID:25930176
Simpson-Holley, Martha; Colgrove, Robert C; Nalepa, Grzegorz; Harper, J Wade; Knipe, David M
2005-10-01
Herpes simplex virus 1 (HSV-1) replicates in the nucleus of host cells and radically alters nuclear architecture as part of its replication process. Replication compartments (RCs) form, and host chromatin is marginalized. Chromatin is later dispersed, and RCs spread past it to reach the nuclear edge. Using a lamin A-green fluorescent protein fusion, we provide direct evidence that the nuclear lamina is disrupted during HSV-1 infection and that the UL31 and UL34 proteins are required for this. We show nuclear expansion from 8 h to 24 h postinfection and place chromatin rearrangement and disruption of the lamina in the context of this global change in nuclear architecture. We show HSV-1-induced disruption of the localization of Cdc14B, a cellular protein and component of a putative nucleoskeleton. We also show that UL31 and UL34 are required for nuclear expansion. Studies with inhibitors of globular actin (G-actin) indicate that G-actin plays an essential role in nuclear expansion and chromatin dispersal but not in lamina alterations induced by HSV-1 infection. From analyses of HSV infections under various conditions, we conclude that nuclear expansion and chromatin dispersal are dispensable for optimal replication, while lamina rearrangement is associated with efficient replication.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Imanishi, Masatoshi; Nakanishi, Kouichiro; Izumi, Takuma, E-mail: masa.imanishi@nao.ac.jp
2016-05-01
We present the results of our ALMA Cycle 2 high angular resolution (0.″1–0.″2) observations of the nuclear region of the nearby well-studied type-2 active galactic nucleus (AGN), NGC 1068, at HCN J = 3–2 and HCO{sup +} J = 3–2 emission lines. For the first time, due to a higher angular resolution than previous studies, we clearly detected dense molecular gas emission at the putative AGN location, identified as a ∼1.1 mm (∼266 GHz) continuum emission peak, by separating this emission from brighter emission located at 0.″5–2.″0 on the eastern and western sides of the AGN. The estimated intrinsic molecularmore » emission size and dense molecular mass, which are thought to be associated with the putative dusty molecular torus around an AGN, were ∼10 pc and ∼several × 10{sup 5} M {sub ⊙}, respectively. HCN-to-HCO{sup +} J = 3–2 flux ratios substantially higher than unity were found throughout the nuclear region of NGC 1068. The continuum emission displayed an elongated morphology along the direction of the radio jet located at the northern side of the AGN, as well as a weak spatially-resolved component at ∼2.″0 on the southwestern side of the AGN. The latter component most likely originated from star formation, with the estimated luminosity more than one order of magnitude lower than the luminosity of the central AGN. No vibrationally excited ( v {sub 2} = 1f) J = 3–2 emission lines were detected for HCN and HCO{sup +} across the field of view.« less
NASA Astrophysics Data System (ADS)
Imanishi, Masatoshi; Nakanishi, Kouichiro; Izumi, Takuma
2016-05-01
We present the results of our ALMA Cycle 2 high angular resolution (0.″1-0.″2) observations of the nuclear region of the nearby well-studied type-2 active galactic nucleus (AGN), NGC 1068, at HCN J = 3-2 and HCO+ J = 3-2 emission lines. For the first time, due to a higher angular resolution than previous studies, we clearly detected dense molecular gas emission at the putative AGN location, identified as a ˜1.1 mm (˜266 GHz) continuum emission peak, by separating this emission from brighter emission located at 0.″5-2.″0 on the eastern and western sides of the AGN. The estimated intrinsic molecular emission size and dense molecular mass, which are thought to be associated with the putative dusty molecular torus around an AGN, were ˜10 pc and ˜several × 105 M ⊙, respectively. HCN-to-HCO+ J = 3-2 flux ratios substantially higher than unity were found throughout the nuclear region of NGC 1068. The continuum emission displayed an elongated morphology along the direction of the radio jet located at the northern side of the AGN, as well as a weak spatially-resolved component at ˜2.″0 on the southwestern side of the AGN. The latter component most likely originated from star formation, with the estimated luminosity more than one order of magnitude lower than the luminosity of the central AGN. No vibrationally excited (v 2 = 1f) J = 3-2 emission lines were detected for HCN and HCO+ across the field of view.
Bénit, Paule; Steffann, Julie; Lebon, Sophie; Chretien, Dominique; Kadhom, Noman; de Lonlay, Pascale; Goldenberg, Alice; Dumez, Yves; Dommergues, Marc; Rustin, Pierre; Munnich, Arnold; Rötig, Agnès
2003-05-01
Complex I deficiency, the most common cause of mitochondrial disorders, accounts for a variety of clinical symptoms and its genetic heterogeneity makes identification of the disease genes particularly tedious. Indeed, most of the 43 complex I subunits are encoded by nuclear genes, only seven of them being mitochondrially encoded. In order to offer urgent prenatal diagnosis, we have studied an inbred/multiplex family with complex I deficiency by using microsatellite DNA markers flanking the putative disease loci. Microsatellite DNA markers have allowed us to exclude the NDUFS7, NDUFS8, NDUFV1 and NDUFS1 genes and to find homozygosity at the NDUFS4 locus. Direct sequencing has led to identification of a homozygous splice acceptor site mutation in intron 1 of the NDUFS4 gene (IVS1nt -1, G-->A); this was not found in chorion villi of the ongoing pregnancy. We suggest that genotyping microsatellite DNA markers at putative disease loci in inbred/multiplex families helps to identify the disease-causing mutation. More generally, we suggest giving consideration to a more systematic microsatellite analysis of putative disease loci for identification of disease genes in inbred/multiplex families affected with genetically heterogeneous conditions.
Todeschi, Maria R; El Backly, Rania M; Varghese, Oommen P; Hilborn, Jöns; Cancedda, Ranieri; Mastrogiacomo, Maddalena
2017-07-01
This study aimed to identify host cell recruitment patterns in a mouse model in response to rhBMP-2 releasing hyaluronic acid hydrogels and influence of added nano-hydroxyapatite particles on rhBMP-2 release and pattern of bone formation. Implanted gels were retrieved after implantation and cells were enzymatically dissociated for flow cytometric analysis. Percentages of macrophages, progenitor endothelial cells and putative mesenchymal stem cells were measured. Implants were evaluated for BMP-2 release by ELISA and by histology to monitor tissue formation. Hyaluronic acid+BMP-2 gels influenced the inflammatory response in the bone healing microenvironment. Host-derived putative mesenchymal stem cells were major contributors. Addition of hydroxyapatite nanoparticles modified the release pattern of rhBMP-2, resulting in enhanced bone formation.
Liu, Guan-Ting; Kung, Hsiu-Ni; Chen, Chung-Kuan; Huang, Cheng; Wang, Yung-Li; Yu, Cheng-Pu; Lee, Chung-Pei
2018-02-26
Although a vesicular nucleocytoplasmic transport system is believed to exist in eukaryotic cells, the features of this pathway are mostly unknown. Here, we report that the BFRF1 protein of the Epstein-Barr virus improves vesicular transport of nuclear envelope (NE) to facilitate the translocation and clearance of nuclear components. BFRF1 expression induces vesicles that selectively transport nuclear components to the cytoplasm. With the use of aggregation-prone proteins as tools, we found that aggregated nuclear proteins are dispersed when these BFRF1-induced vesicles are formed. BFRF1-containing vesicles engulf the NE-associated aggregates, exit through from the NE, and putatively fuse with autophagic vacuoles. Chemical treatment and genetic ablation of autophagy-related factors indicate that autophagosome formation and autophagy-linked FYVE protein-mediated autophagic proteolysis are involved in this selective clearance of nuclear proteins. Remarkably, vesicular transport, elicited by BFRF1, also attenuated nuclear aggregates accumulated in neuroblastoma cells. Accordingly, induction of NE-derived vesicles by BFRF1 facilitates nuclear protein translocation and clearance, suggesting that autophagy-coupled transport of nucleus-derived vesicles can be elicited for nuclear component catabolism in mammalian cells.-Liu, G.-T., Kung, H.-N., Chen, C.-K., Huang, C., Wang, Y.-L., Yu, C.-P., Lee, C.-P. Improving nuclear envelope dynamics by EBV BFRF1 facilitates intranuclear component clearance through autophagy.
Krosch, Matt N; Strutt, Francesca; Blacket, Mark J; Batovska, Jana; Starkie, Melissa; Clarke, Anthony R; Cameron, Stephen L; Schutze, Mark K
2018-06-06
Accurate species-level identifications underpin many aspects of basic and applied biology; however, identifications can be hampered by a lack of discriminating morphological characters, taxonomic expertise or time. Molecular approaches, such as DNA 'barcoding' of the cytochrome c oxidase (COI) gene, are argued to overcome these issues. However, nuclear encoding of mitochondrial genes (numts) and poor amplification success of suboptimally preserved specimens can lead to erroneous identifications. One insect group for which these molecular and morphological problems are significant are the dacine fruit flies (Diptera: Tephritidae: Dacini). We addressed these issues associated with COI barcoding in the dacines by first assessing several 'universal' COI primers against public mitochondrial genome and numt sequences for dacine taxa. We then modified a set of four primers that more closely matched true dacine COI sequence and amplified two overlapping portions of the COI barcode region. Our new primers were tested alongside universal primers on a selection of dacine species, including both fresh preserved and decades-old dry specimens. Additionally, Bactrocera tryoni mitochondrial and nuclear genomes were compared to identify putative numts. Four numt clades were identified, three of which were amplified using existing universal primers. In contrast, our new primers preferentially amplified the 'true' mitochondrial COI barcode in all dacine species tested. The new primers also successfully amplified partial barcodes from dry specimens for which full length barcodes were unobtainable. Thus we recommend these new primers be incorporated into the suites of primers used by diagnosticians and quarantine labs for the accurate identification of dacine species. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Characterization of muscle ankyrin repeat proteins in human skeletal muscle.
Wette, Stefan G; Smith, Heather K; Lamb, Graham D; Murphy, Robyn M
2017-09-01
Muscle ankyrin repeat proteins (MARPs) are a family of titin-associated, stress-response molecules and putative transducers of stretch-induced signaling in skeletal muscle. In cardiac muscle, cardiac ankyrin repeat protein (CARP) and diabetes-related ankyrin repeat protein (DARP) reportedly redistribute from binding sites on titin to the nucleus following a prolonged stretch. However, it is unclear whether ankyrin repeat domain protein 2 (Ankrd 2) shows comparable stretch-induced redistribution to the nucleus. We measured the following in rested human skeletal muscle: 1 ) the absolute amount of MARPs and 2 ) the distribution of Ankrd 2 and DARP in both single fibers and whole muscle preparations. In absolute amounts, Ankrd 2 is the most abundant MARP in human skeletal muscle, there being ~3.1 µmol/kg, much greater than DARP and CARP (~0.11 and ~0.02 µmol/kg, respectively). All DARP was found to be tightly bound at cytoskeletal (or possibly nuclear) sites. In contrast, ~70% of the total Ankrd 2 is freely diffusible in the cytosol [including virtually all of the phosphorylated (p)Ankrd 2-Ser99 form], ~15% is bound to non-nuclear membranes, and ~15% is bound at cytoskeletal sites, likely at the N2A region of titin. These data are not consistent with the proposal that Ankrd 2, per se, or pAnkrd 2-Ser99 mediates stretch-induced signaling in skeletal muscle, dissociating from titin and translocating to the nucleus, because the majority of these forms of Ankrd 2 are already free in the cytosol. It will be necessary to show that the titin-associated Ankrd 2 is modified by stretch in some as-yet-unidentified way, distinct from the diffusible pool, if it is to act as a stretch-sensitive signaling molecule. Copyright © 2017 the American Physiological Society.
Tsujimoto, Yayoi; Numaga, Takuro; Ohshima, Kiyoshi; Yano, Masa-aki; Ohsawa, Ryuji; Goto, Derek B.; Naito, Satoshi; Ishikawa, Masayuki
2003-01-01
The tom2-1 mutation of Arabidopsis thaliana reduces the efficiency of intracellular multiplication of tobamoviruses. The tom2-1 mutant was derived from fast-neutron-irradiated seeds, and the original mutant line also carries ttm1, a dominant modifier that increases tobamovirus multiplication efficiency in a tobamovirus-strain-specific manner in the tom2-1 genetic background. Here, we show that the tom2-1 mutation involved a deletion of ∼20 kb in the nuclear genome. The deleted region included two genes named TOM2A and TOM2B that were both associated with the tom2-1 phenotype, whereas ttm1 corresponded to the translocation of part of the deleted region that included intact TOM2B but not TOM2A. TOM2A encodes a 280 amino acid putative four-pass transmembrane protein with a C-terminal farnesylation signal, while TOM2B encodes a 122 amino acid basic protein. The split-ubiquitin assay demonstrated an interaction of TOM2A both with itself and with TOM1, an integral membrane protein of A.thaliana presumed to be an essential constituent of tobamovirus replication complex. The data presented here suggest that TOM2A is also an integral part of the tobamovirus replication complex. PMID:12514139
The MB2 gene family of Plasmodium species has a unique combination of S1 and GTP-binding domains
Romero, Lisa C; Nguyen, Thanh V; Deville, Benoit; Ogunjumo, Oluwasanmi; James, Anthony A
2004-01-01
Background Identification and characterization of novel Plasmodium gene families is necessary for developing new anti-malarial therapeutics. The products of the Plasmodium falciparum gene, MB2, were shown previously to have a stage-specific pattern of subcellular localization and proteolytic processing. Results Genes homologous to MB2 were identified in five additional parasite species, P. knowlesi, P. gallinaceum, P. berghei, P. yoelii, and P. chabaudi. Sequence comparisons among the MB2 gene products reveal amino acid conservation of structural features, including putative S1 and GTP-binding domains, and putative signal peptides and nuclear localization signals. Conclusions The combination of domains is unique to this gene family and indicates that MB2 genes comprise a novel family and therefore may be a good target for drug development. PMID:15222903
0610009K11Rik, a testis-specific and germ cell nuclear receptor-interacting protein
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang Heng; Denhard, Leslie A.; Zhou Huaxin
Using an in silico approach, a putative nuclear receptor-interacting protein 0610009K11Rik was identified in mouse testis. We named this gene testis-specific nuclear receptor-interacting protein-1 (Tnrip-1). Tnrip-1 was predominantly expressed in the testis of adult mouse tissues. Expression of Tnrip-1 in the testis was regulated during postnatal development, with robust expression in 14-day-old or older testes. In situ hybridization analyses showed that Tnrip-1 is highly expressed in pachytene spermatocytes and spermatids. Consistent with its mRNA expression, Tnrip-1 protein was detected in adult mouse testes. Immunohistochemical studies showed that Tnrip-1 is a nuclear protein and mainly expressed in pachytene spermatocytes and roundmore » spermatids. Moreover, co-immunoprecipitation analyses showed that endogenous Tnrip-1 protein can interact with germ cell nuclear receptor (GCNF) in adult mouse testes. Our results suggest that Tnrip-1 is a testis-specific and GCNF-interacting protein which may be involved in the modulation of GCNF-mediated gene transcription in spermatogenic cells within the testis.« less
Nuclear Glycolytic Enzyme Enolase of Toxoplasma gondii Functions as a Transcriptional Regulator
Mouveaux, Thomas; Oria, Gabrielle; Werkmeister, Elisabeth; Slomianny, Christian; Fox, Barbara A.; Bzik, David J.; Tomavo, Stanislas
2014-01-01
Apicomplexan parasites including Toxoplasma gondii have complex life cycles within different hosts and their infectivity relies on their capacity to regulate gene expression. However, little is known about the nuclear factors that regulate gene expression in these pathogens. Here, we report that T. gondii enolase TgENO2 is targeted to the nucleus of actively replicating parasites, where it specifically binds to nuclear chromatin in vivo. Using a ChIP-Seq technique, we provide evidence for TgENO2 enrichment at the 5′ untranslated gene regions containing the putative promoters of 241 nuclear genes. Ectopic expression of HA-tagged TgENO1 or TgENO2 led to changes in transcript levels of numerous gene targets. Targeted disruption of TgENO1 gene results in a decrease in brain cyst burden of chronically infected mice and in changes in transcript levels of several nuclear genes. Complementation of this knockout mutant with ectopic TgENO1-HA fully restored normal transcript levels. Our findings reveal that enolase functions extend beyond glycolytic activity and include a direct role in coordinating gene regulation in T. gondii. PMID:25153525
DOE Office of Scientific and Technical Information (OSTI.GOV)
Inagaki, Yuichi; Mitsutake, Susumu; Igarashi, Yasuyuki
2006-05-12
Retinitis pigmentosa (RP) is a genetically heterogeneous disease characterized by degeneration of the retina. A mutation in a new ceramide kinase (CERK) homologous gene, named CERK-like protein (CERKL), was found to cause autosomal recessive retinitis pigmentosa (RP26). Here, we show a point mutation of one of two putative nuclear localization signal (NLS) sequences inhibited the nuclear localization of the protein. Furthermore, the tetra-GFP-tagged NLS, which cannot passively enter the nucleus, was observed not only in the nucleus but also in the nucleolus. Our results provide First evidence of the active nuclear import of CERKL and suggest that the identified NLSmore » might be responsible for nucleolar retention of the protein. As recent studies have shown other RP-related proteins are localized in the nucleus or the nucleolus, our identification of NLS in CERKL suggests that CERKL likely plays important roles for retinal functions in the nucleus and the nucleolus.« less
Non-senescent Hydra tolerates severe disturbances in the nuclear lamina.
Klimovich, Alexander; Rehm, Arvid; Wittlieb, Jörg; Herbst, Eva-Maria; Benavente, Ricardo; Bosch, Thomas C G
2018-05-10
The cnidarian Hydra is known for its unlimited lifespan and non-senescence, due to the indefinite self-renewal capacity of its stem cells. While proteins of the Lamin family are recognized as critical factors affecting senescence and longevity in human and mice, their putative role in the extreme longevity and non-senescence in long-living animals remains unknown. Here we analyze the role of a single lamin protein in non-senescence of Hydra . We demonstrate that proliferation of stem cells in Hydra is robust against the disturbance of Lamin expression and localization. While Lamin is indispensable for Hydra , the stem cells tolerate overexpression, downregulation and mislocalization of Lamin, and disturbances in the nuclear envelope structure. This extraordinary robustness may underlie the indefinite self-renewal capacity of stem cells and the non-senescence of Hydra . A relatively low complexity of the nuclear envelope architecture in basal Metazoa might allow for their extreme lifespans, while an increasing complexity of the nuclear architecture in bilaterians resulted in restricted lifespans.
Cyclophilin B enhances HIV-1 Infection
DeBoer, Jason; Madson, Christian J.; Belshan, Michael
2016-01-01
Cyclophilin B (CypB) is a member of the immunophilin family and intracellular chaperone. It predominantly localizes to the ER, but also contains a nuclear localization signal and is secreted from cells. CypB has been shown to interact with the Gag protein of human immunodeficiency type 1 (HIV-1). Several proteomic and genetic studies identified it as a potential factor involved in HIV replication. Herein, we show that over-expression of CypB enhances HIV infection by increasing nuclear import of viral DNA. This enhancement was unaffected by cyclosporine treatment and requires the N-terminus of the protein. The N-terminus contains an ER leader sequence, putative nuclear localization signal, and is required for secretion. Deletion of the N-terminus resulted in mislocalization from the ER and suppression of HIV infection. Passive transfer experiments showed that secreted CypB did not impact HIV infection. Combined, these experiments show that intracellular CypB modulates a pathway of HIV nuclear import. PMID:26774171
Cyclophilin B enhances HIV-1 infection.
DeBoer, Jason; Madson, Christian J; Belshan, Michael
2016-02-01
Cyclophilin B (CypB) is a member of the immunophilin family and intracellular chaperone. It predominantly localizes to the ER, but also contains a nuclear localization signal and is secreted from cells. CypB has been shown to interact with the Gag protein of human immunodeficiency type 1 (HIV-1). Several proteomic and genetic studies identified it as a potential factor involved in HIV replication. Herein, we show that over-expression of CypB enhances HIV infection by increasing nuclear import of viral DNA. This enhancement was unaffected by cyclosporine treatment and requires the N-terminus of the protein. The N-terminus contains an ER leader sequence, putative nuclear localization signal, and is required for secretion. Deletion of the N-terminus resulted in mislocalization from the ER and suppression of HIV infection. Passive transfer experiments showed that secreted CypB did not impact HIV infection. Combined, these experiments show that intracellular CypB modulates a pathway of HIV nuclear import. Copyright © 2015 Elsevier Inc. All rights reserved.
Non-senescent Hydra tolerates severe disturbances in the nuclear lamina
Rehm, Arvid; Wittlieb, Jörg; Herbst, Eva-Maria; Benavente, Ricardo
2018-01-01
The cnidarian Hydra is known for its unlimited lifespan and non-senescence, due to the indefinite self-renewal capacity of its stem cells. While proteins of the Lamin family are recognized as critical factors affecting senescence and longevity in human and mice, their putative role in the extreme longevity and non-senescence in long-living animals remains unknown. Here we analyze the role of a single lamin protein in non-senescence of Hydra. We demonstrate that proliferation of stem cells in Hydra is robust against the disturbance of Lamin expression and localization. While Lamin is indispensable for Hydra, the stem cells tolerate overexpression, downregulation and mislocalization of Lamin, and disturbances in the nuclear envelope structure. This extraordinary robustness may underlie the indefinite self-renewal capacity of stem cells and the non-senescence of Hydra. A relatively low complexity of the nuclear envelope architecture in basal Metazoa might allow for their extreme lifespans, while an increasing complexity of the nuclear architecture in bilaterians resulted in restricted lifespans. PMID:29754147
DOE Office of Scientific and Technical Information (OSTI.GOV)
La Cognata, M., E-mail: lacognata@lns.infn.it; Kiss, G. G.; Mukhamedzhanov, A. M.
2015-10-15
Resonances in nuclear cross sections dramatically change their trends. Therefore, the presence of unexpected resonances might lead to unpredicted consequences on astrophysics and nuclear physics. In nuclear physics, resonances allow one to study states in the intermediate compound systems, to evaluate their cluster structure, for instance, especially in the energy regions approaching particle decay thresholds. In astrophysics, resonances might lead to changes in the nucleosynthesis flow, determining different isotopic compositions of the nuclear burning ashes. For these reasons, the Trojan Horse method has been modified to investigate resonant reactions. Thanks to this novel approach, for the first time normalization tomore » direct data might be avoided. Moreover, in the case of sub threshold resonances, the Trojan Horse method modified to investigate resonances allows one to deduce the asymptotic normalization coefficient, showing the close connection between the two indirect approaches.« less
Phylogeny of Eleusine (Poaceae: Chloridoideae) based on nuclear ITS and plastid trnT-trnF sequences.
Neves, Susana S; Swire-Clark, Ginger; Hilu, Khidir W; Baird, Wm Vance
2005-05-01
Phylogenetic relationships in the genus Eleusine (Poaceae: Chloridoideae) were investigated using nuclear ITS and plastid trnT-trnF sequences. Separate and combined data sets were analyzed using parsimony, distance, and likelihood based methods, including Bayesian. Data congruence was examined using character and topological measures. Significant data heterogeneity was detected, but there was little conflict in the topological substructure measures for triplets and quartets, and resolution and clade support increased in the combined analysis. Data incongruence may be a result of noise and insufficient information in the slower evolving trnT-trnF. Monophyly of Eleusine is strongly supported in all analyses, but basal relationships in the genus remain uncertain. There is good support for a CAIK clade (E. coracana subsp. coracana and africana, E. indica, and E. kigeziensis), with E. tristachya as its sister group. Two putative ITS homeologues (A and B loci) were identified in the allotetraploid E. coracana; the 'B' locus sequence type was not found in the remaining species. Eleusine coracana and its putative 'A' genome donor, the diploid E. indica, are confirmed close allies, but sequence data contradicts the hypothesis that E. floccifolia is its second genome donor. The 'B' genome donor remains unidentified and may be extinct.
Plant U13 orthologues and orphan snoRNAs identified by RNomics of RNA from Arabidopsis nucleoli
Kim, Sang Hyon; Spensley, Mark; Choi, Seung Kook; Calixto, Cristiane P. G.; Pendle, Ali F.; Koroleva, Olga; Shaw, Peter J.; Brown, John W. S.
2010-01-01
Small nucleolar RNAs (snoRNAs) and small Cajal body-specific RNAs (scaRNAs) are non-coding RNAs whose main function in eukaryotes is to guide the modification of nucleotides in ribosomal and spliceosomal small nuclear RNAs, respectively. Full-length sequences of Arabidopsis snoRNAs and scaRNAs have been obtained from cDNA libraries of capped and uncapped small RNAs using RNA from isolated nucleoli from Arabidopsis cell cultures. We have identified 31 novel snoRNA genes (9 box C/D and 22 box H/ACA) and 15 new variants of previously described snoRNAs. Three related capped snoRNAs with a distinct gene organization and structure were identified as orthologues of animal U13snoRNAs. In addition, eight of the novel genes had no complementarity to rRNAs or snRNAs and are therefore putative orphan snoRNAs potentially reflecting wider functions for these RNAs. The nucleolar localization of a number of the snoRNAs and the localization to nuclear bodies of two putative scaRNAs was confirmed by in situ hybridization. The majority of the novel snoRNA genes were found in new gene clusters or as part of previously described clusters. These results expand the repertoire of Arabidopsis snoRNAs to 188 snoRNA genes with 294 gene variants. PMID:20081206
Beyond detection: nuclear physics with a webcam in an educational setting
NASA Astrophysics Data System (ADS)
Pallone, Arthur
2015-03-01
Nuclear physics affects our daily lives in such diverse fields from medicine to art. I believe three obstacles - limited time, lack of subject familiarity and thus comfort on the part of educators, and equipment expense - must be overcome to produce a nuclear-educated populace. Educators regularly use webcams to actively engage students in scientific discovery as evidenced by a literature search for the term webcam paired with topics such as astronomy, biology, and physics. Inspired by YouTube videos that demonstrate alpha particle detection by modified webcams, I searched for examples that go beyond simple detection with only one education-oriented result - the determination of the in-air range of alphas using a modified CCD camera. Custom-built, radiation-hardened CMOS detectors exist in high energy physics and for soft x-ray detection. Commercial CMOS cameras are used for direct imaging in electron microscopy. I demonstrate charged-particle spectrometry with a slightly modified CMOS-based webcam. When used with inexpensive sources of radiation and free software, the webcam charged-particle spectrometer presents educators with a simple, low-cost technique to include nuclear physics in science education.
Fission control system for nuclear reactor
Conley, G.H.; Estes, G.P.
Control system for nuclear reactor comprises a first set of reactivity modifying rods fixed in a reactor core with their upper ends stepped in height across the core, and a second set of reactivity modifying rods movable vertically within the reactor core and having their lower ends stepped to correspond with the stepped arrangement of the first set of rods, pairs of the rods of the first and second sets being in coaxial alignment.
Advancing Precision Nuclear Medicine and Molecular Imaging for Lymphoma.
Wright, Chadwick L; Maly, Joseph J; Zhang, Jun; Knopp, Michael V
2017-01-01
PET with fluorodeoxyglucose F 18 ( 18 F FDG-PET) is a meaningful biomarker for the detection, targeted biopsy, and treatment of lymphoma. This article reviews the evolution of 18 F FDG-PET as a putative biomarker for lymphoma and addresses the current capabilities, challenges, and opportunities to enable precision medicine practices for lymphoma. Precision nuclear medicine is driven by new imaging technologies and methodologies to more accurately detect malignant disease. Although quantitative assessment of response is limited, such technologies will enable a more precise metabolic mapping with much higher definition image detail and thus may make it a robust and valid quantitative response assessment methodology. Copyright © 2016 Elsevier Inc. All rights reserved.
Evidence of Nuclear Disks from the Radial Distribution of CCSNe in Starburst Galaxies
NASA Astrophysics Data System (ADS)
Herrero-Illana, Rubén; Pérez-Torres, Miguel Ángel; Alberdi, Antxon
Galaxy-galaxy interactions are expected to be responsible for triggering massive star formation and possibly accretion onto a supermassive black hole, by providing large amounts of dense molecular gas down to the central kiloparsec region. Several scenarios to drive the gas further down to the central ˜ 100 pc, have been proposed, including the formation of a nuclear disk around the black hole, where massive stars would produce supernovae. Here, we probe the radial distribution of supernovae and supernova remnants in the nuclear regions of the starburst galaxies M82, Arp 299-A, and Arp 220, by using high-angular resolution (≲ 0.'1) radio observations. We derived scale-length values for the putative nuclear disks, which range from ˜ 20-30 pc for Arp 299-A and Arp 220, up to ˜ 140 pc for M82. The radial distribution of SNe for the nuclear disks in Arp 299-A and Arp 220 is also consistent with a power-law surface density profile of exponent γ = 1, as expected from detailed hydrodynamical simulations of nuclear disks. This study is detailed in Herrero-Illana, Perez-Torres, and Alberdi [11].
Chakrabarti, Rajarshi; Bhowmick, Debajit; Bhargava, Varsha; Bhar, Kaushik; Siddhanta, Anirban
2013-09-20
Phosphatidylinositol 4 phosphate 5 kinase 1α (PIP5K) is mainly localized in the cytosol and plasma membrane. Studies have also indicated its prominent association with nuclear speckles. The exact nature of this nuclear pool of PIP5K is not clear. Using biochemical and microscopic techniques, we have demonstrated that the nuclear pool of PIP5K is modified by SUMO-1 in HEK-293 cells stably expressing PIP5K. Moreover, this SUMOylated pool of PIP5K increased during apoptosis. PolySUMO-2 chain conjugated PIP5K was detected by pull-down experiment using affinity-tagged RNF4, a polySUMO-2 binding protein, during late apoptosis. Copyright © 2013 Elsevier Inc. All rights reserved.
SkyNet: Modular nuclear reaction network library
NASA Astrophysics Data System (ADS)
Lippuner, Jonas; Roberts, Luke F.
2017-10-01
The general-purpose nuclear reaction network SkyNet evolves the abundances of nuclear species under the influence of nuclear reactions. SkyNet can be used to compute the nucleosynthesis evolution in all astrophysical scenarios where nucleosynthesis occurs. Any list of isotopes can be evolved and SkyNet supports various different types of nuclear reactions. SkyNet is modular, permitting new or existing physics, such as nuclear reactions or equations of state, to be easily added or modified.
Peroxide-modified titanium dioxide: a chemical analog of putative Martian soil oxidants
NASA Technical Reports Server (NTRS)
Quinn, R. C.; Zent, A. P.
1999-01-01
Hydrogen peroxide chemisorbed on titanium dioxide (peroxide-modified titanium dioxide) is investigated as a chemical analog to the putative soil oxidants responsible for the chemical reactivity seen in the Viking biology experiments. When peroxide-modified titanium dioxide (anatase) was exposed to a solution similar to the Viking labeled release (LR) experiment organic medium, CO2 gas was released into the sample cell headspace. Storage of these samples at 10 degrees C for 48 hr prior to exposure to organics resulted in a positive response while storage for 7 days did not. In the Viking LR experiment, storage of the Martian surface samples for 2 sols (approximately 49 hr) resulted in a positive response while storage for 141 sols essentially eliminated the initial rapid release of CO2. Heating the peroxide-modified titanium dioxide to 50 degrees C prior to exposure to organics resulted in a negative response. This is similar to, but not identical to, the Viking samples where heating to approximately 46 degrees C diminished the response by 54-80% and heating to 51.5 apparently eliminated the response. When exposed to water vapor, the peroxide-modified titanium dioxide samples release O2 in a manner similar to the release seen in the Viking gas exchange experiment (GEx). Reactivity is retained upon heating at 50 degrees C for three hours, distinguishing this active agent from the one responsible for the release of CO2 from aqueous organics. The release of CO2 by the peroxide-modified titanium dioxide is attributed to the decomposition of organics by outer-sphere peroxide complexes associated with surface hydroxyl groups, while the release of O2 upon humidification is attributed to more stable inner-sphere peroxide complexes associated with Ti4+ cations. Heating the peroxide-modified titanium dioxide to 145 degrees C inhibited the release of O2, while in the Viking experiments heating to this temperature diminished but did not eliminated the response. Although the thermal stability of the titanium-peroxide complexes in this work is lower than the stability seen in the Viking experiments, it is expected that similar types of complexes will form in titanium containing minerals other than anatase and the stability of these complexes will vary with surface hydroxylation and mineralogy.
Yu, Seok-Ho; Boyce, Michael; Wands, Amberlyn M.; Bond, Michelle R.; Bertozzi, Carolyn R.; Kohler, Jennifer J.
2012-01-01
O-linked β-N-acetylglucosamine (O-GlcNAc) is a reversible posttranslational modification found on hundreds of nuclear and cytoplasmic proteins in higher eukaryotes. Despite its ubiquity and essentiality in mammals, functional roles for the O-GlcNAc modification remain poorly defined. Here we develop a combined genetic and chemical approach that enables introduction of the diazirine photocrosslinker onto the O-GlcNAc modification in cells. We engineered mammalian cells to produce diazirine-modified O-GlcNAc by expressing a mutant form of UDP-GlcNAc pyrophosphorylase and subsequently culturing these cells with a cell-permeable, diazirine-modified form of GlcNAc-1-phosphate. Irradiation of cells with UV light activated the crosslinker, resulting in formation of covalent bonds between O-GlcNAc-modified proteins and neighboring molecules, which could be identified by mass spectrometry. We used this method to identify interaction partners for the O-GlcNAc-modified FG-repeat nucleoporins. We observed crosslinking between FG-repeat nucleoporins and nuclear transport factors, suggesting that O-GlcNAc residues are intimately associated with essential recognition events in nuclear transport. Further, we propose that the method reported here could find widespread use in investigating the functional consequences of O-GlcNAcylation. PMID:22411826
Mapping Sites of O-Glycosylation and Fringe Elongation on Drosophila Notch*
Harvey, Beth M.; Rana, Nadia A.; Moss, Hillary; Leonardi, Jessica; Jafar-Nejad, Hamed; Haltiwanger, Robert S.
2016-01-01
Glycosylation of the Notch receptor is essential for its activity and serves as an important modulator of signaling. Three major forms of O-glycosylation are predicted to occur at consensus sites within the epidermal growth factor-like repeats in the extracellular domain of the receptor: O-fucosylation, O-glucosylation, and O-GlcNAcylation. We have performed comprehensive mass spectral analyses of these three types of O-glycosylation on Drosophila Notch produced in S2 cells and identified peptides containing all 22 predicted O-fucose sites, all 18 predicted O-glucose sites, and all 18 putative O-GlcNAc sites. Using semiquantitative mass spectral methods, we have evaluated the occupancy and relative amounts of glycans at each site. The majority of the O-fucose sites were modified to high stoichiometries. Upon expression of the β3-N-acetylglucosaminyltransferase Fringe with Notch, we observed varying degrees of elongation beyond O-fucose monosaccharide, indicating that Fringe preferentially modifies certain sites more than others. Rumi modified O-glucose sites to high stoichiometries, although elongation of the O-glucose was site-specific. Although the current putative consensus sequence for O-GlcNAcylation predicts 18 O-GlcNAc sites on Notch, we only observed apparent O-GlcNAc modification at five sites. In addition, we performed mass spectral analysis on endogenous Notch purified from Drosophila embryos and found that the glycosylation states were similar to those found on Notch from S2 cells. These data provide foundational information for future studies investigating the mechanisms of how O-glycosylation regulates Notch activity. PMID:27268051
Reiman, Eric M.; Chen, Kewei; Caselli, Richard J.; Alexander, Gene E.; Bandy, Daniel; Adamson, Jennifer L.; Lee, Wendy; Cannon, Ashley; Stephan, Elizabeth A.; Stephan, Dietrich A.; Papassotiropoulos, Andreas
2008-01-01
We recently implicated a cluster of nine single nucleotide polymorphisms from seven cholesterol-related genes in the risk of Alzheimer’s disease (AD) in a European cohort, and we proposed calculating an aggregate cholesterol-related genetic score (CREGS) to characterize a person’s risk. In a separate study, we found that apolipoprotein E (APOE) ε4 gene dose, an established AD risk factor, was correlated with fluorodeoxyglucose (FDG) positron emission tomography (PET) measurements of hypometabolism in AD-affected brain regions in a cognitively normal American cohort, and we proposed using PET as a presymptomatic endophenotype to help assess putative modifiers of AD risk. Thus, the objective in the present study is to determine whether CREGS is related to PET measurements of hypometabolism in AD-affected brain regions. DNA and PET data from 141 cognitively normal late middle-aged APOE ε4 homozygotes, heterozygotes and non-carriers were analyzed to evaluate the relationship between CREGS and regional PET measurements. Cholesterol-related genetic risk scores were associated with hypometabolism in AD-affected brain regions, even when controlling for the effects of APOE ε4 gene dose. The results support the role of cholesterol-related genes in the predisposition to AD, and support the value of neuroimaging in the presymptomatic assessment of putative modifiers of AD risk. PMID:18280754
Federal Register 2010, 2011, 2012, 2013, 2014
2010-06-28
... University (the licensee, WSU) to operate the Washington State University Modified TRIGA Nuclear Radiation... NUCLEAR REGULATORY COMMISSION [Docket No. 50-27; Facility Operating License No. R-76; NRC-2010... Safeguards Information and Sensitive Unclassified Non-Safeguards Information AGENCY: Nuclear Regulatory...
Hamady, Zaed Z R; Farrar, Mark D; Whitehead, Terence R; Holland, Keith T; Lodge, J Peter A; Carding, Simon R
2008-10-01
The use of genetically modified bacteria to deliver biologically active molecules directly to the gut has become an increasingly attractive area of investigation. The challenge of regulation of production of the therapeutic molecule and colonization of the bowel led us to investigate Bacteroides ovatus for the production of these molecules, due to its ability to colonize the colon and xylan utilization properties. Here we have identified the putative xylanase promoter. The 5' region of the corresponding mRNA was determined by 5'RACE analysis and the transcription initiation site was identified 216 bp upstream of the ATG start codon. The putative xylanase promoter was regulated by xylan in a dose- and time-dependent manner, and repressed by glucose. This promoter was subsequently used to direct the controlled expression of a gene encoding the human intestinal trefoil factor (TFF-3) after integration as a single copy into the chromosome of B. ovatus. The resulting strain produced biologically active TFF-3 in the presence of xylan. These findings identify the B. ovatus xylanase operon promoter and show that it can be utilized to direct xylan-inducible expression of heterologous eukaryotic genes in B. ovatus.
Thermal stability of G-rich anti-parallel DNA triplexes upon insertion of LNA and α-L-LNA.
Kosbar, Tamer R; Sofan, Mamdouh A; Abou-Zeid, Laila; Pedersen, Erik B
2015-05-14
G-rich anti-parallel DNA triplexes were modified with LNA or α-L-LNA in their Watson-Crick and TFO strands. The triplexes were formed by targeting a pyrimidine strand to a putative hairpin formed by Hoogsteen base pairing in order to use the UV melting method to evaluate the stability of the triplexes. Their thermal stability was reduced when the TFO strand was modified with LNA or α-L-LNA. The same trend was observed when the TFO strand and the purine Watson-Crick strand both were modified with LNA. When all triad components were modified with α-L-LNA and LNA in the middle of the triplex, the thermal melting was increased. When the pyrimidine sequence was modified with a single insertion of LNA or α-L-LNA the ΔTm increased. Moreover, increasing the number of α-L-LNA in the pyrimidine target sequence to six insertions, leads to a high increase in the thermal stability. The conformational S-type structure of α-L-LNA in anti-parallel triplexes is preferable for triplex stability.
The Role ERG and CXCR4 in Prostate Cancer Progression
2011-06-01
axis functions in PC progression to enhance invasion and metastasis. To address the regulation of CXCR4 expression, we identified several putative ERG...interaction between ERG factor and CXCR4 gene promoter and link these activities with TMPRSS2-ERG translocations and enhanced metastasis of tumor cells via...and increased VCaP nuclear extract protein in assay enhanced the intensity of bands (Figure 1D). Inclusion of anti-ERG antibodies super shifted
Czubryt, M P; Russell, J C; Sarantopoulos, J; Gilchrist, J S; Pierce, G N
1997-11-01
The putative role of the nuclear nucleoside triphosphatase (NTPase) is to provide energy to the nuclear pore complex for poly A(+) mRNA export. Previous work has demonstrated that liver nuclear NTPase activity is greater in 6 month old corpulent (cp/cp) female JCR:LA rats, a hyperlipidemic rat model, compared to lean (+/?) animals. This increase appeared to be related to increases in nuclear membrane cholesterol content. The current study extended these initial data to compare NTPase activity as a function of age and sex in isolated JCR:LA-cp rat liver nuclei, to further test the hypothesis that nuclear membrane cholesterol may modulate NTPase activity. NTPase activity was increased in cp/cp female animals compared to +/? females at all ages studied, with Vmax values increased by 60-176%. Membrane integrity of cp/cp female nuclei was reduced compared to +/? female nuclei. Nuclear membrane cholesterol levels increased linearly with age by 50, 150 and 250% in 3, 6 and 9 month old cp/cp females over leans. In contrast, nuclei from cp/cp males exhibited only minor, isolated changes in NTPase activity. Furthermore, there were no significant changes in nuclear cholesterol content or membrane integrity in the less hyperlipidemic male animals at any age. These data suggest that altered lipid metabolism may lead to changes in nuclear membrane structure, which in turn may alter NTPase activity and functioning of the nuclear pore complex.
Atypical nuclear localization of VIP receptors in glioma cell lines and patients
DOE Office of Scientific and Technical Information (OSTI.GOV)
Barbarin, Alice; Séité, Paule; Godet, Julie
Highlights: • The VIP receptor VPAC1 contains a putative NLS signal. • VPAC1 is predominantly nuclear in GBM cell lines but not VPAC2. • Non-nuclear VPAC1/2 protein expression is correlated with glioma grade. • Nuclear VPAC1 is observed in 50% of stage IV glioma (GBM). - Abstract: An increasing number of G protein-coupled receptors, like receptors for vasoactive intestinal peptide (VIP), are found in cell nucleus. As VIP receptors are involved in the regulation of glioma cell proliferation and migration, we investigated the expression and the nuclear localization of the VIP receptors VPAC1 and VPAC2 in this cancer. First, bymore » applying Western blot and immunofluorescence detection in three human glioblastoma (GBM) cell lines, we observed a strong nuclear staining for the VPAC1 receptor and a weak nuclear VPAC2 receptor staining. Second, immunohistochemical staining of VPAC1 and VPAC2 on tissue microarrays (TMA) showed that the two receptors were expressed in normal brain and glioma tissues. Expression in the non-nuclear compartment of the two receptors significantly increased with the grade of the tumors. Analysis of nuclear staining revealed a significant increase of VPAC1 staining with glioma grade, with up to 50% of GBM displaying strong VPAC1 nuclear staining, whereas nuclear VPAC2 staining remained marginal. The increase in VPAC receptor expression with glioma grades and the enhanced nuclear localization of the VPAC1 receptors in GBM might be of importance for glioma progression.« less
The Measurement of Nuclear War Attitudes: Methods and Concerns.
ERIC Educational Resources Information Center
Mayton, Daniel M., II
Measures of adults' attitudes toward nuclear war are briefly discussed, and Mayton's Modified World Affairs Questionnaire (MWAQ) is described. The 23-item MWAQ was developed from Novak and Lerner's World Affairs Questionnaire, a nuclear war attitude measure by Mayton and Delamater, and related interview items by Jeffries. When the MWAQ was…
Bogacheva, Mariia; Egorova, Anna; Slita, Anna; Maretina, Marianna; Baranov, Vladislav; Kiselev, Anton
2017-11-01
The major barriers for intracellular DNA transportation by cationic polymers are their toxicity, poor endosomal escape and inefficient nuclear uptake. Therefore, we designed novel modular peptide-based carriers modified with SV40 nuclear localization signal (NLS). Core peptide consists of arginine, histidine and cysteine residues for DNA condensation, endosomal escape promotion and interpeptide cross-linking, respectively. We investigated three polyplexes with different NLS content (10 mol%, 50 mol% and 90 mol% of SV40 NLS) as vectors for intranuclear DNA delivery. All carriers tested were able to condense DNA, to protect it from DNAase I and were not toxic to the cells. We observed that cell cycle arrest by hydroxyurea did not affect transfection efficacy of NLS-modified carriers which we confirmed using quantitative confocal microscopy analysis. Overall, peptide carrier modified with 90 mol% of SV40 NLS provided efficient transfection and nuclear uptake in non-dividing cells. Thus, incorporation of NLS into arginine-rich cross-linking peptides is an adequate approach to the development of efficient intranuclear gene delivery vehicles. Copyright © 2017 Elsevier Ltd. All rights reserved.
Byrne, C; Miclet, E; Broutin, I; Gallo, D; Pelekanou, V; Kampa, M; Castanas, E; Leclercq, G; Jacquot, Y
2013-10-01
Protein-protein interactions are crucial for signal transductions required for cell differentiation and proliferation. Their modulation is therefore key to the development of therapeutic alternatives, particularly in the context of cancer. According to literature data, the polyproline-rich nuclear receptor coactivators PNRC and PNRC2 interact with estrogen receptor (ERα) through their PxxP SH3-binding motifs. In a search to identify the molecular features governing this interaction, we explored using electronic circular dichroism (ECD) spectroscopy and molecular dynamics (MD) calculations, the capacity of a range of putative biologically active peptides derived from these proteins and containing this PxxP motif(s) to form polyproline II (PPII) domains. An additional more exhaustive structural study on a lead PPII peptide was also performed using 2D nuclear magnetic resonance (NMR) spectroscopy. With the exception of one of all the investigated peptides (PNRC-D), binding assays failed to detect any affinity for Grb2 SH3 domains, suggesting that PPII motifs issued from Grb2 antagonists have a binding mode distinct from those derived from Grb2 agonists. Instead, the peptides revealed a competitive binding ability against a synthetic peptide (ERα17p) with a putative PPII-cognate domain located within a coregulator recruitment region of ERα (AF-2 site). Our work, which constitutes the first structure-related interaction study concerning PNRC and PNRC2, supports not only the existence of PxxP-induced PPII sequences in these coregulators, but also confirms the presence of a PPII recognition site in the AF-2 of the steroid receptor ERα, a region important for transcription regulation. © 2013 Wiley Periodicals, Inc.
Kucejová, B; Foury, F
2003-01-01
RIM1 is a nuclear gene of the yeast Saccharomyces cerevisiae coding for a protein with single-stranded DNA-binding activity that is essential for mitochondrial genome maintenance. No protein partners of Rim1p have been described so far in yeast. To better understand the role of this protein in mitochondrial DNA replication and recombination, a search for protein interactors by the yeast two-hybrid system was performed. This approach led to the identification of several candidates, including a putative transcription factor, Azf1p, and Mph1p, a protein with an RNA helicase domain which is known to influence the mutation rate of nuclear and mitochondrial genomes.
2011-01-01
Background The genus Pyrus belongs to the tribe Pyreae (the former subfamily Maloideae) of the family Rosaceae, and includes one of the most important commercial fruit crops, pear. The phylogeny of Pyrus has not been definitively reconstructed. In our previous efforts, the internal transcribed spacer region (ITS) revealed a poorly resolved phylogeny due to non-concerted evolution of nrDNA arrays. Therefore, introns of low copy nuclear genes (LCNG) are explored here for improved resolution. However, paralogs and lineage sorting are still two challenges for applying LCNGs in phylogenetic studies, and at least two independent nuclear loci should be compared. In this work the second intron of LEAFY and the alcohol dehydrogenase gene (Adh) were selected to investigate their molecular evolution and phylogenetic utility. Results DNA sequence analyses revealed a complex ortholog and paralog structure of Adh genes in Pyrus and Malus, the pears and apples. Comparisons between sequences from RT-PCR and genomic PCR indicate that some Adh homologs are putatively nonfunctional. A partial region of Adh1 was sequenced for 18 Pyrus species and three subparalogs representing Adh1-1 were identified. These led to poorly resolved phylogenies due to low sequence divergence and the inclusion of putative recombinants. For the second intron of LEAFY, multiple inparalogs were discovered for both LFY1int2 and LFY2int2. LFY1int2 is inadequate for phylogenetic analysis due to lineage sorting of two inparalogs. LFY2int2-N, however, showed a relatively high sequence divergence and led to the best-resolved phylogeny. This study documents the coexistence of outparalogs and inparalogs, and lineage sorting of these paralogs and orthologous copies. It reveals putative recombinants that can lead to incorrect phylogenetic inferences, and presents an improved phylogenetic resolution of Pyrus using LFY2int2-N. Conclusions Our study represents the first phylogenetic analyses based on LCNGs in Pyrus. Ancient and recent duplications lead to a complex structure of Adh outparalogs and inparalogs in Pyrus and Malus, resulting in neofunctionalization, nonfunctionalization and possible subfunctionalization. Among all investigated orthologs, LFY2int2-N is the best nuclear marker for phylogenetic reconstruction of Pyrus due to suitable sequence divergence and the absence of lineage sorting. PMID:21917170
Alphavirus replicon approach to promoterless analysis of IRES elements.
Kamrud, K I; Custer, M; Dudek, J M; Owens, G; Alterson, K D; Lee, J S; Groebner, J L; Smith, J F
2007-04-10
Here we describe a system for promoterless analysis of putative internal ribosome entry site (IRES) elements using an alphavirus (family Togaviridae) replicon vector. The system uses the alphavirus subgenomic promoter to produce transcripts that, when modified to contain a spacer region upstream of an IRES element, allow analysis of cap-independent translation of genes of interest (GOI). If the IRES element is removed, translation of the subgenomic transcript can be reduced >95% compared to the same transcript containing a functional IRES element. Alphavirus replicons, used in this manner, offer an alternative to standard dicistronic DNA vectors or in vitro translation systems currently used to analyze putative IRES elements. In addition, protein expression levels varied depending on the spacer element located upstream of each IRES. The ability to modulate the level of expression from alphavirus vectors should extend the utility of these vectors in vaccine development.
Alphavirus Replicon Approach to Promoterless Analysis of IRES Elements
Kamrud, K.I.; Custer, M.; Dudek, J.M.; Owens, G.; Alterson, K.D.; Lee, J.S.; Groebner, J.L.; Smith, J.F.
2007-01-01
Here we describe a system for promoterless analysis of putative internal ribosome entry site (IRES) elements using an alphavirus (Family Togaviridae) replicon vector. The system uses the alphavirus subgenomic promoter to produce transcripts that, when modified to contain a spacer region upstream of an IRES element, allow analysis of cap-independent translation of genes of interest (GOI). If the IRES element is removed, translation of the subgenomic transcript can be reduced > 95 % compared to the same transcript containing a functional IRES element. Alphavirus replicons, used in this manner, offer an alternative to standard dicistronic DNA vectors or in-vitro translation systems currently used to analyze putative IRES elements. In addition, protein expression levels varied depending on the spacer element located upstream of each IRES. The ability to modulate the level of expression from alphavirus vectors should extend the utility of these vectors in vaccine development. PMID:17156813
Interband interference effects at the edge of a multiband chiral p -wave superconductor
NASA Astrophysics Data System (ADS)
Zhang, Jia-Long; Huang, Wen; Sigrist, Manfred; Yao, Dao-Xin
2017-12-01
Chiral superconductors support chiral edge modes and potentially spontaneous edge currents at their boundaries. Motivated by the putative multiband chiral p -wave superconductor Sr2RuO4 , we study the influence of the interference between different bands at the edges, which may appear in the presence of moderate edge disorder or in edge tunneling measurements. We show that interband interference can strongly modify the measurable quantities at the edges when the order parameter exhibits phase difference between the bands. This is illustrated by investigating the edge dispersion and the edge current distribution in the presence of interband mixing, as well as the conductance at a tunneling junction. The results are discussed in connection with the putative chiral p -wave superconductor Sr2RuO4 . In passing, we also discuss similar interference effects in multiband models with other pairing symmetries.
Boulila, Moncef
2010-06-01
To enhance the knowledge of recombination as an evolutionary process, 267 accessions retrieved from GenBank were investigated, all belonging to five economically important viruses infecting fruit crops (Plum pox, Apple chlorotic leaf spot, Apple mosaic, Prune dwarf, and Prunus necrotic ringspot viruses). Putative recombinational events were detected in the coat protein (CP)-encoding gene using RECCO and RDP version 3.31beta algorithms. Based on RECCO results, all five viruses were shown to contain potential recombination signals in the CP gene. Reconstructed trees with modified topologies were proposed. Furthermore, RECCO performed better than the RDP package in detecting recombination events and exhibiting their evolution rate along the sequences of the five viruses. RDP, however, provided the possible major and minor parents of the recombinants. Thus, the two methods should be considered complementary.
Connections of intermediate filaments with the nuclear lamina and the cell periphery.
Katsuma, Y; Swierenga, S H; Marceau, N; French, S W
1987-01-01
We investigated the relationship between intermediate filaments (IFs) and other detergent- and nuclease-resistant filamentous structures of cultured liver epithelial cells (T51B cell line) using whole mount unembedded preparations which were sequentially extracted with Triton X-100 and nucleases. Immunogold labelling and stereoscopic observation facilitated the examination of each filamentous structure and their three-dimensional relationships to each other. After solubilizing phospholipid, nucleic acid and soluble cellular protein, the resulting cytoskeleton preparation consisted of a network of cytokeratin and vimentin IFs linked by 3 nm filaments. The IFs were anchored to and determined the position of the nuclear lamina filaments (NLF) network and the centrioles. The NLF was composed of the nuclear lamina filaments measuring 3-6 nm in diameter which radiated from and anchored to the skeleton of the nuclear pores. The IFs located in the nuclear region appeared to be interwoven with the NLF. At the cell surface, the IFs seemed to be attached to the putative actin filament network. They formed a focally interrupted plexus-like structure at the cell periphery. Fragments of vimentin filaments were found among the filamentous network located at the cell surface, and some filaments terminated blindly there.
Phosphorylation of zona occludens-2 by protein kinase C epsilon regulates its nuclear exportation.
Chamorro, David; Alarcón, Lourdes; Ponce, Arturo; Tapia, Rocio; González-Aguilar, Héctor; Robles-Flores, Martha; Mejía-Castillo, Teresa; Segovia, José; Bandala, Yamir; Juaristi, Eusebio; González-Mariscal, Lorenza
2009-09-01
Here, we have analyzed the subcellular destiny of newly synthesized tight junction protein zona occludens (ZO)-2. After transfection in sparse cells, 74% of cells exhibit ZO-2 at the nucleus, and after 18 h the value decreases to 17%. The mutation S369A located within the nuclear exportation signal 1 of ZO-2 impairs the nuclear export of the protein. Because Ser369 represents a putative protein kinase C (PKC) phosphorylation site, we tested the effect of PKC inhibition and stimulation on the nuclear export of ZO-2. Our results strongly suggest that the departure of ZO-2 from the nucleus is regulated by phosphorylation at Ser369 by novel PKCepsilon. To test the route taken by ZO-2 from synthesis to the plasma membrane, we devised a novel nuclear microinjection assay in which the nucleus served as a reservoir for anti-ZO-2 antibody. Through this assay, we demonstrate that a significant amount of newly synthesized ZO-2 goes into the nucleus and is later relocated to the plasma membrane. These results constitute novel information for understanding the mechanisms that regulate the intracellular fate of ZO-2.
Dutta, Rahul; Malakar, Dhruba; Khate, Keviletsu; Sahu, Shailendra; Akshey, Yogesh; Mukesh, Manishi
2011-09-15
The main purpose of the experiment was to compare the efficiency of three cell types, namely adult fibroblast, putative embryonic stem (ES) cell, and lymphocyte, as donor cells for somatic cell nuclear transfer by handmade cloning in goats. The outcome clearly shows that putative embryonic stem cells, with a cleavage and blastocyst production rate of 74.69% ± 3.92 and 39.75% ± 3.86, respectively, performs better in comparison to adult fibroblast cell and lymphocyte. Between adult fibroblast cell and lymphocyte no statistically significant difference exists at P < 0.05. An overall cleavage and blastocyst formation rate of 67.41% ± 3.92 and 26.96% ± 3.86 was obtained using adult fibroblast donor cells. The study establishes beyond doubt the reprogrammability of lymphocyte by handmade cloning (HMC) protocol with a cleavage and blastocyst production rate of 56.47% ± 3.92 and 24.70% ± 3.86, respectively. PCR analysis of highly polymorphic 286 bp fragment of MHC II DRB genes of cloned embryos and three donor cells were performed to verify the cloned embryos. The amplified PCR products were subjected to SSCP to confirm their genetic identity. The karyotyping of the cloned embryos showed normal chromosomal status as expected in goat. Significantly, in the second stage of the experiment, the produced cloned embryos were successfully used to derive ntES-like cells. The rate of primary colony formation rate was 62.50% ± 4.62 for fibroblast donor cell derived embryos. The same was 60.60% ± 4.62 for putative ES donor cell derived embryos and 66.66% ± 4.62 for lymphocyte donor cell derived embryos, respectively. The putative ntES colonies were positively characterized for alkaline phosphatase, Oct-4, TRA-1-60, TRA-1-81, Sox-2, and Nanog by Immunocytochemistry and Reverse Transcription PCR. To further validate the stem ness, the produced putative ntES colonies were differentiated to embryoid bodies. Immunocytochemistry revealed that embryoid bodies expressed NESTIN specific for ectodermal lineage; GATA-4 for endodermal lineage and smooth muscle actin-I, and troponin-I specific for mesodermal lineage. The study has established an efficient protocol for putative ntES cell derivation from HMC embryos. It could be of substantial significance as patient specific ntES cells have proven therapeutic significance. Copyright © 2011 Elsevier Inc. All rights reserved.
Identification and characterization of putative stem cells in the adult pig ovary.
Bui, Hong-Thuy; Van Thuan, Nguyen; Kwon, Deug-Nam; Choi, Yun-Jung; Kang, Min-Hee; Han, Jae-Woong; Kim, Teoan; Kim, Jin-Hoi
2014-06-01
Recently, the concept of 'neo-oogenesis' has received increasing attention, since it was shown that adult mammals have a renewable source of eggs. The purpose of this study was to elucidate the origin of these eggs and to confirm whether neo-oogenesis continues throughout life in the ovaries of the adult mammal. Adult female pigs were utilized to isolate, identify and characterize, including their proliferation and differentiation capabilities, putative stem cells (PSCs) from the ovary. PSCs were found to comprise a heterogeneous population based on c-kit expression and cell size, and also express stem and germ cell markers. Analysis of PSC molecular progression during establishment showed that these cells undergo cytoplasmic-to-nuclear translocation of Oct4 in a manner reminiscent of gonadal primordial germ cells (PGCs). Hence, cells with the characteristics of early PGCs are present or are generated in the adult pig ovary. Furthermore, the in vitro establishment of porcine PSCs required the presence of ovarian cell-derived extracellular regulatory factors, which are also likely to direct stem cell niche interactions in vivo. In conclusion, the present work supports a crucial role for c-kit and kit ligand/stem cell factor in stimulating the growth, proliferation and nuclear reprogramming of porcine PSCs, and further suggests that porcine PSCs might be the culture equivalent of early PGCs. © 2014. Published by The Company of Biologists Ltd.
Winokur, S T; Shiang, R
1998-11-01
The TCOF1 gene product, treacle, responsible for the craniofacial disorder Treacher Collins syndrome, has been predicted to be a member of a class of nucleolar phosphoproteins based on its primary amino acid sequence. Treacle is a low complexity protein with ten repeating units of acidic and basic residues, each of which contains a large number of putative casein kinase 2 and protein kinase C phosphorylation sites. In addition, the C-terminus of treacle contains multiple putative nuclear localization signals. The overall structure of treacle, as well as sequence similarity to several nucleolar phosphoproteins, predicts that treacle is a member of this class of proteins. Using green fluorescent protein fusion constructs with the full-length and deleted domains of the murine homolog of treacle, we demonstrate that the cellular localization of treacle is nucleolar. This localization is mediated by the last 41 residues of the C-terminus (residues 1262-1302). At least two functional nuclear localization signals have been identified in the protein, one between residues 1176 and 1270 and the second within the last 32 residues of the protein (1271-1302). The nucleolar localization signal is disrupted by two constructs that split the C-terminal region between residues 1270 and 1271. This study provides the first direct analysis of treacle and demonstrates that the protein involved in TCOF1 is a nucleolar protein.
Liu, Tingli; Ye, Wenwu; Ru, Yanyan; Yang, Xinyu; Gu, Biao; Tao, Kai; Lu, Shan; Dong, Suomeng; Zheng, Xiaobo; Shan, Weixing; Wang, Yuanchao; Dou, Daolong
2011-01-01
Phytophthora sojae encodes hundreds of putative host cytoplasmic effectors with conserved FLAK motifs following signal peptides, termed crinkling- and necrosis-inducing proteins (CRN) or Crinkler. Their functions and mechanisms in pathogenesis are mostly unknown. Here, we identify a group of five P. sojae-specific CRN-like genes with high levels of sequence similarity, of which three are putative pseudogenes. Functional analysis shows that the two functional genes encode proteins with predicted nuclear localization signals that induce contrasting responses when expressed in Nicotiana benthamiana and soybean (Glycine max). PsCRN63 induces cell death, while PsCRN115 suppresses cell death elicited by the P. sojae necrosis-inducing protein (PsojNIP) or PsCRN63. Expression of CRN fragments with deleted signal peptides and FLAK motifs demonstrates that the carboxyl-terminal portions of PsCRN63 or PsCRN115 are sufficient for their activities. However, the predicted nuclear localization signal is required for PsCRN63 to induce cell death but not for PsCRN115 to suppress cell death. Furthermore, silencing of the PsCRN63 and PsCRN115 genes in P. sojae stable transformants leads to a reduction of virulence on soybean. Intriguingly, the silenced transformants lose the ability to suppress host cell death and callose deposition on inoculated plants. These results suggest a role for CRN effectors in the suppression of host defense responses.
Wierk, Jannika Katharina; Langbehn, Annette; Kamper, Maria; Richter, Stefanie; Burda, Paul-Christian; Heussler, Volker Theo; Deschermeier, Christina
2013-01-01
Mitogen-activated protein kinases (MAPKs) regulate key signaling events in eukaryotic cells. In the genomes of protozoan Plasmodium parasites, the causative agents of malaria, two genes encoding kinases with significant homology to other eukaryotic MAPKs have been identified (mapk1, mapk2). In this work, we show that both genes are transcribed during Plasmodium berghei liver stage development, and analyze expression and subcellular localization of the PbMAPK1 protein in liver stage parasites. Live cell imaging of transgenic parasites expressing GFP-tagged PbMAPK1 revealed a nuclear localization of PbMAPK1 in the early schizont stage mediated by nuclear localization signals in the C-terminal domain. In contrast, a distinct localization of PbMAPK1 in comma/ring-shaped structures in proximity to the parasite’s nuclei and the invaginating parasite membrane was observed during the cytomere stage of parasite development as well as in immature blood stage schizonts. The PbMAPK1 localization was found to be independent of integrity of a motif putatively involved in ATP binding, integrity of the putative activation motif and the presence of a predicted coiled-coil domain in the C-terminal domain. Although PbMAPK1 knock out parasites showed normal liver stage development, the kinase may still fulfill a dual function in both schizogony and merogony of liver stage parasites regulated by its dynamic and stage-dependent subcellular localization. PMID:23544094
Lorentz-violating contributions to the nuclear Schiff moment and nuclear EDM
NASA Astrophysics Data System (ADS)
Araujo, Jonas B.; Casana, Rodolfo; Ferreira, Manoel M.
2018-03-01
In the context of an atom endowed with nuclear electric dipole moments (EDM), we consider the effects on the Schiff moment of C P T -even Lorentz-violating (LV) terms that modify the Coulomb potential. First, we study the modifications on the Schiff moment when the nucleus interacts with the electronic cloud by means of a Coulomb potential altered only by the P -even LV components. Next, by supposing the existence of an additional intrinsic LV EDM generated by other LV sources, we assess the corrections to the Schiff moment when the interaction nucleus-electrons runs mediated by a Coulomb potential modified by both the P -odd and P -even LV components. We then use known estimates and EDM measurements to discuss upper bounds on the new Schiff moment components and the possibility of a nuclear EDM component ascribed to LV effects.
Germline Genetic Modification and Identity: the Mitochondrial and Nuclear Genomes.
Scott, Rosamund; Wilkinson, Stephen
2017-12-01
In a legal 'first', the UK removed a prohibition against modifying embryos in human reproduction, to enable mitochondrial replacement techniques (MRTs), a move the Government distanced from 'germline genetic modification', which it aligned with modifying the nuclear genome. This paper (1) analyzes the uses and meanings of this term in UK/US legal and policy debates; and (2) evaluates related ethical concerns about identity. It shows that, with respect to identity, MRTs and nuclear genome editing techniques such as CRISPR/Cas-9 (now a policy topic), are not as different as has been supposed. While it does not follow that the two should be treated exactly alike, one of the central reasons offered for treating MRTs more permissively than nuclear genetic modification, and for not regarding MRTs as 'germline genetic modification', is thereby in doubt. Identity cannot, by itself, do the work thus far assigned to it, explicitly or otherwise, in law and policy.
Visalli, Robert J.; Nicolosi, Denise M.; Irven, Karen L.; Goshorn, Bradley; Khan, Tamseel; Visalli, Melissa A.
2007-01-01
The putative DNA encapsidation genes encoded by open reading frames (ORFs) 25, 26, 30, 34, 43, 45/42 and 54 were cloned from Varicella-zoster virus (VZV) strain Ellen. Sequencing revealed that the Ellen ORFs were highly conserved at the amino acid level when compared to those of nineteen previously published VZV isolates. Additionally, RT-PCR provided the first evidence that ORF45/42 was expressed as a spliced transcript in VZV-infected cells. All seven ORFs were expressed in vitro and full length products were identified using a C-terminal V5 epitope tag. The in vitro products of the putative VZV terminase subunits encoded by ORFs 30 and 45/42 proved useful in protein-protein interaction assays. Previous studies have reported the formation of a heterodimeric terminase complex involved in DNA encapsidation for both herpes simplex virus-type 1 (HSV-1) and human cytomegalovirus (HCMV). Here we report that the C-terminal portion of exon II of ORF45/42 (ORF42-C269) interacted in GST-pull down experiments with in vitro synthesized ORF30 and ORF45/42. The interactions were maintained in the presence of anionic detergents and in buffers of increasing ionic strength. Cells transiently transfected with epitope tagged ORF45/42 or ORF30 showed primarily cytoplasmic staining. In contrast, an antiserum directed to the N-terminal portion of ORF45 showed nearly exclusive nuclear localization of the ORF45/42 gene product in infected cells. An ORF30 specific antiserum detected an 87 kDa protein in both the cytoplasmic and nuclear fractions of VZV infected cells. The results were consistent with the localization and function of herpesviral terminase subunits. This is the first study aimed at the identification and characterization of the VZV DNA encapsidation gene products. PMID:17868947
Yu, Jiaojun; Kuroda, Chiaki; Gong, Xun
2014-01-01
Natural hybridization has been considered to represent an important factor influencing the high diversity of the genus Ligularia Cass. in the Hengduan Mountains, China. Natural hybridization has been confirmed to occur frequently in Ligularia. To date, however, it has been demonstrated only within a single population. In this paper, we present evidence of natural hybridization in Ligularia from four different locations. The internal transcribed spacer (ITS) region of the nuclear ribosomal DNA and three chloroplast intergenic spacers (trnK-rps16, trnL-rpl32 and trnQ-5'rps16) of 149 accessions of putative hybrids and their putative parents (L. cymbulifera and L. tongolensis) were analyzed for evidence of hybridization. The ITS data clearly distinguished two putative parental species and sympatric L. vellerea and supported the hypothesis that those morphological intermediates were products of natural hybridization between L. cymbulifera and L. tongolensis. Moreover, several identified morphological parents were actual introgressed products. Because of hybridization and introgression, chloroplast DNA sequences generated a poorly resolved network. The present results indicate that varying degrees of hybridization and introgression occur differently depending on the habitat context. We conclude that gene flow caused by natural hybridization in Ligularia indeed plays an important role in the species diversity.
A proteomic study of the arabidopsis nuclear matrix.
Calikowski, Tomasz T; Meulia, Tea; Meier, Iris
2003-10-01
The eukaryotic nucleus has been proposed to be organized by two interdependent nucleoprotein structures, the DNA-based chromatin and the RNA-dependent nuclear matrix. The functional composition and molecular organization of the second component have not yet been resolved. Here, we describe the isolation of the nuclear matrix from the model plant Arabidopsis, its initial characterization by confocal and electron microscopy, and the identification of 36 proteins by mass spectrometry. Electron microscopy of resinless samples confirmed a structure very similar to that described for the animal nuclear matrix. Two-dimensional gel electrophoresis resolved approximately 300 protein spots. Proteins were identified in batches by ESI tandem mass spectrometry after resolution by 1D SDS-PAGE. Among the identified proteins were a number of demonstrated or predicted Arabidopsis homologs of nucleolar proteins such as IMP4, Nop56, Nop58, fibrillarins, nucleolin, as well as ribosomal components and a putative histone deacetylase. Others included homologs of eEF-1, HSP/HSC70, and DnaJ, which have also been identified in the nucleolus or nuclear matrix of human cells, as well as a number of novel proteins with unknown function. This study is the first proteomic approach towards the characterization of a higher plant nuclear matrix. It demonstrates the striking similarities both in structure and protein composition of the operationally defined nuclear matrix across kingdoms whose unicellular ancestors have separated more than one billion years ago. Copyright 2003 Wiley-Liss, Inc.
mRNA export: threading the needle
Gaouar, Ouassila; Germain, Hugo
2013-01-01
After mRNA biogenesis, several proteins interact with the messenger to ensure its proper export to the cytoplasm. Some of these proteins will bind RNA early on, at the onset of transcription by RNA polymerase II holoenzyme, while others will join later for downstream processing steps, such as poly-adenylation or splicing, or may direct mRNA ribonucleoprotein particle migration to the nucleopore. We recently discovered that Arabidopsis plant knockout for the protein MOS11 (MODIFIER OF SNC1, 11) partially suppresses autoimmune responses observed in the TNL-type [TIR/NBS/LRR (Toll-interleukin-like receptor/nucleotide-binding site/C-terminal leucine-rich repeat)] R gene gain-of-function variant snc1 (suppressor of npr1-1, constitutive 1). This suppression of resistance to pathogens appears to be caused by a decrease in nuclear mRNA export in mos11-1 snc1 plants. In humans, the putative ortholog of MOS11, CIP29 (29-kDa cytokine-induced protein), interacts with three proteins that are also involved in mRNA export: DDX39 (DEAD-box RNA helicase), TAF15 of the FUS family (FUSED IN SARCOMA), and ALY (ALWAYS EARLY), a protein implicated in mRNA export in mammalian systems. These proteins have received very little attention in plants. Here, we will discuss their particularities and role in mRNA export and biotic stress. PMID:23526740
Pathogenesis of Germline and Somatic NF1 Rearrangements
1998-10-01
skin and skeletal features consistent with a connective tissue disorder and neoplasms at a young age (7, 8, 9, 10) To test this hypothesis, patients need... myeloproliferative phenotype, these data suggest a putative role of modifying gene(s) on chromosome 17 that may contribute to the development of acute...risk for certain types of neoplasms , NF1 subjects also have an increased risk of developing a second malignancy. The risk for NF l patients is 8-20
Agronomic performance of Populus deltoides trees engineered for biofuel production
Macaya-Sanz, David; Chen, Jin?Gui; Kalluri, Udaya C.; ...
2017-11-30
Background: One of the major barriers to the development of lignocellulosic feedstocks is the recalcitrance of plant cell walls to deconstruction and saccharification. Recalcitrance can be reduced by targeting genes involved in cell wall biosynthesis, but this can have unintended consequences that compromise the agronomic performance of the trees under field conditions. Here we report the results of a field trial of fourteen distinct transgenic Populus deltoides lines that had previously demonstrated reduced recalcitrance without yield penalties under greenhouse conditions.Results: Survival and productivity of the trial were excellent in the first year, and there was little evidence for reduced performancemore » of the transgenic lines with modified target gene expression. Surprisingly, the most striking phenotypic effects in this trial were for two empty-vector control lines that had modified bud set and bud flush. This is most likely due to somaclonal variation or insertional mutagenesis. Traits related to yield, crown architecture, herbivory, pathogen response, and frost damage showed few significant differences between target gene transgenics and empty vector controls. However, there were a few interesting exceptions. Lines overexpressing the DUF231 gene, a putative O-acetyltransferase, showed early bud flush and marginally increased height growth. Lines overexpressing the DUF266 gene, a putative glycosyltransferase, had significantly decreased stem internode length and slightly higher volume index. Finally, lines overexpressing the PFD2 gene, a putative member of the prefoldin complex, had a slightly reduced volume index.Conclusions: This field trial demonstrates that these cell wall modifications, which decreased cell wall recalcitrance under laboratory conditions, did not seriously compromise first-year performance in the field, despite substantial challenges, including an outbreak of a stem boring insect (Gypsonoma haimbachiana), attack by a leaf rust pathogen (Melampsora spp.), and a late frost event. This bodes well for the potential utility of these lines as advanced biofuels feedstocks.« less
Agronomic performance of Populus deltoides trees engineered for biofuel production
DOE Office of Scientific and Technical Information (OSTI.GOV)
Macaya-Sanz, David; Chen, Jin?Gui; Kalluri, Udaya C.
Background: One of the major barriers to the development of lignocellulosic feedstocks is the recalcitrance of plant cell walls to deconstruction and saccharification. Recalcitrance can be reduced by targeting genes involved in cell wall biosynthesis, but this can have unintended consequences that compromise the agronomic performance of the trees under field conditions. Here we report the results of a field trial of fourteen distinct transgenic Populus deltoides lines that had previously demonstrated reduced recalcitrance without yield penalties under greenhouse conditions.Results: Survival and productivity of the trial were excellent in the first year, and there was little evidence for reduced performancemore » of the transgenic lines with modified target gene expression. Surprisingly, the most striking phenotypic effects in this trial were for two empty-vector control lines that had modified bud set and bud flush. This is most likely due to somaclonal variation or insertional mutagenesis. Traits related to yield, crown architecture, herbivory, pathogen response, and frost damage showed few significant differences between target gene transgenics and empty vector controls. However, there were a few interesting exceptions. Lines overexpressing the DUF231 gene, a putative O-acetyltransferase, showed early bud flush and marginally increased height growth. Lines overexpressing the DUF266 gene, a putative glycosyltransferase, had significantly decreased stem internode length and slightly higher volume index. Finally, lines overexpressing the PFD2 gene, a putative member of the prefoldin complex, had a slightly reduced volume index.Conclusions: This field trial demonstrates that these cell wall modifications, which decreased cell wall recalcitrance under laboratory conditions, did not seriously compromise first-year performance in the field, despite substantial challenges, including an outbreak of a stem boring insect (Gypsonoma haimbachiana), attack by a leaf rust pathogen (Melampsora spp.), and a late frost event. This bodes well for the potential utility of these lines as advanced biofuels feedstocks.« less
Bazzani, Lorenzo; Donnini, Sandra; Giachetti, Antonio; Christofori, Gerhard; Ziche, Marina
2018-01-01
Prostaglandin E2 (PGE2) contributes to tumor progression by promoting cancer cell growth, invasion and by creating a favorable pro-tumor microenvironment. PGE2 has been reported to transactivate and internalize into the nucleus receptor tyrosine kinases such as Epidermal growth factor receptor (EGFR), thereby supporting tumor progression. Here we demonstrate that in non-small cell lung carcinoma (NSCLC) cells, PGE2 induces EGFR nuclear translocation via different dynamin-dependent endocytic pathways, promotes the formation of an EGFR-STAT3 complex, affects nuclear EGFR target gene expression and mediates tumor cell proliferation. Indeed, we find that PGE2 induces EGFR internalization and consequent nuclear import through Clathrin- and Caveolin-mediated endocytosis and through the interaction of EGFR with Importin β1. Within the nucleus, EGFR forms a complex with STAT3, an event blocked by ablation of Clathrin Heavy Chain or Caveolin-1. The combination of EGF and PGE2 prolongs nuclear EGFR transcriptional activity manifested by the upregulation of CCND1, PTGS2, MYC and NOS2 mRNA levels and potentiates nuclear EGFR-induced NSCLC cell proliferation. Additionally, NSCLC patients with high expression of a nuclear EGFR gene signature display shorter survival times than those with low expression, thus showing a putative correlation between nuclear EGFR and poor prognosis in NSCLC. Together, our findings indicate a complex mechanism underlying PGE2-induced EGF/EGFR signaling and transcriptional control, which plays a key role in cancer progression. PMID:29599917
Lee, Kenneth K.; Gruenbaum, Yosef; Spann, Perah; Liu, Jun; Wilson, Katherine L.
2000-01-01
Emerin, MAN1, and LAP2 are integral membrane proteins of the vertebrate nuclear envelope. They share a 43-residue N-terminal motif termed the LEM domain. We found three putative LEM domain genes in Caenorhabditis elegans, designated emr-1, lem-2, and lem-3. We analyzed emr-l, which encodes Ce-emerin, and lem-2, which encodes Ce-MAN1. Ce-emerin and Ce-MAN1 migrate on SDS-PAGE as 17- and 52-kDa proteins, respectively. Based on their biochemical extraction properties and immunolocalization, both Ce-emerin and Ce-MAN1 are integral membrane proteins localized at the nuclear envelope. We used antibodies against Ce-MAN1, Ce-emerin, nucleoporins, and Ce-lamin to determine the timing of nuclear envelope breakdown during mitosis in C. elegans. The C. elegans nuclear envelope disassembles very late compared with vertebrates and Drosophila. The nuclear membranes remained intact everywhere except near spindle poles during metaphase and early anaphase, fully disassembling only during mid-late anaphase. Disassembly of pore complexes, and to a lesser extent the lamina, depended on embryo age: pore complexes were absent during metaphase in >30-cell embryos but existed until anaphase in 2- to 24-cell embryos. Intranuclear mRNA splicing factors disassembled after prophase. The timing of nuclear disassembly in C. elegans is novel and may reflect its evolutionary position between unicellular and more complex eukaryotes. PMID:10982402
Bazzani, Lorenzo; Donnini, Sandra; Giachetti, Antonio; Christofori, Gerhard; Ziche, Marina
2018-03-13
Prostaglandin E 2 (PGE 2 ) contributes to tumor progression by promoting cancer cell growth, invasion and by creating a favorable pro-tumor microenvironment. PGE 2 has been reported to transactivate and internalize into the nucleus receptor tyrosine kinases such as Epidermal growth factor receptor (EGFR), thereby supporting tumor progression. Here we demonstrate that in non-small cell lung carcinoma (NSCLC) cells, PGE 2 induces EGFR nuclear translocation via different dynamin-dependent endocytic pathways, promotes the formation of an EGFR-STAT3 complex, affects nuclear EGFR target gene expression and mediates tumor cell proliferation. Indeed, we find that PGE 2 induces EGFR internalization and consequent nuclear import through Clathrin- and Caveolin-mediated endocytosis and through the interaction of EGFR with Importin β1. Within the nucleus, EGFR forms a complex with STAT3, an event blocked by ablation of Clathrin Heavy Chain or Caveolin-1. The combination of EGF and PGE 2 prolongs nuclear EGFR transcriptional activity manifested by the upregulation of CCND1 , PTGS2 , MYC and NOS2 mRNA levels and potentiates nuclear EGFR-induced NSCLC cell proliferation. Additionally, NSCLC patients with high expression of a nuclear EGFR gene signature display shorter survival times than those with low expression, thus showing a putative correlation between nuclear EGFR and poor prognosis in NSCLC. Together, our findings indicate a complex mechanism underlying PGE 2 -induced EGF/EGFR signaling and transcriptional control, which plays a key role in cancer progression.
Ma, Zhen; Ge, Liya; Lee, Anna S Y; Yong, Jean Wan Hong; Tan, Swee Ngin; Ong, Eng Shi
2008-03-10
Coconut (Cocos nucifera L.) water, which contains many uncharacterized phytohormones is extensively used as a growth promoting supplement in plant tissue culture. In this paper, a high-performance liquid chromatography (HPLC) method was developed for the simultaneous determination of various classes phytohormones, including indole-3-acetic acid (IAA), indole-3-butyric acid (IBA), abscisic acid (ABA), gibberellic acid (GA), zeatin (Z), N(6)-benzyladenine (BA), alpha-naphthaleneacetic acid (NAA) and 2,4-dichlorophenoxyacetic acid (2,4-D) in young coconut water (CW). The analysis was carried out using a reverse-phase HPLC gradient elution, with an aqueous mobile phase (containing 0.1% formic acid, pH adjusted to 3.2 with triethylamine (TEA)) modified by methanol, and solute detection made at 265 nm wavelength. The method was validated for specificity, quantification, accuracy and precision. After preconcentration of putative endogenous phytohormones in CW using C(18) solid-phase extraction (SPE) cartridges, the HPLC method was able to screen for putative endogenous phytohormones present in CW. Finally, the identities of the putative phytohormones present in CW were further confirmed using independent liquid chromatography-tandem mass spectrometry (LC-MS/MS) equipped with an electrospray ionization (ESI) interface.
75 FR 4879 - Juan E. Pérez Monté, M.D.; Confirmatory Order Modifying License (Effective Immediately)
Federal Register 2010, 2011, 2012, 2013, 2014
2010-01-29
... the Health Physics Society, and the Journal of Nuclear Medicine; and, 2. Dr. P[eacute]rez will also... national meetings of the Health Physics Society and the Society of Nuclear Medicine. If the request to make... following: Galenus (Puerto Rico), the Journal of the Health Physics Society, and the Journal of Nuclear...
Cimmino, Flora; Spano, Daniela; Capasso, Mario; Zambrano, Nicola; Russo, Roberta; Zollo, Massimo; Iolascon, Achille
2007-07-01
Neuroblastoma (NB) is an infant tumor which frequently differentiates into neurons. We used two-dimensional differential in-gel electrophoresis (2D-DIGE) to analyze the cytosolic and nuclear protein expression patterns of LAN-5 cells following neuronal differentiating agent all-trans-retinoic acid treatment. We identified several candidate proteins, from which G beta2 and Prefoldin 3 may have a role on NB development. These results strength the use of proteomics to discover new putative protein targets in cancer.
Healthy Diets and the Subsequent Prevalence of Nuclear Cataract in Women
Mares, Julie A.; Voland, Rick; Adler, Rachel; Tinker, Lesley; Millen, AE; Moeller, Suzen M.; Blodi, Barbara; Gehrs, Karen M.; Wallace, Robert B.; Chappell, Richard J.; Neuhouser, Marian L.; Sarto, G
2009-01-01
Objective and Design The association between healthy diet scores which reflect adherence to the US Dietary Guidelines and prevalence of nuclear cataract, assessed four to seven years later, was assessed in a sample of Women's Health Initiative (WHI) Observational Study participants (50–79 years of age) who were residing in Iowa, Wisconsin and Oregon. Scores on the 1995 Healthy Eating Index (HEI-95), which reflect adherence to 1990 guidelines, were assigned from responses to food frequency questionnaires at WHI-baseline (1994–1998). Presence of nuclear cataract was determined from slit-lamp photographs and self-report of cataract extractions were assessed from 2001–04 in the Carotenoids in Age-Related Eye Disease Study (N=1,808). Results Having a high HEI-95 score was the strongest modifiable predictor of low prevalence of nuclear cataract among numerous risk factors investigated in this sample. The multivariable-adjusted OR and 95% confidence interval for high vs. low quintile for diet score were 0.6 (0.4–0.9). Higher prevalence of nuclear cataract was also associated with other modifiable factors (smoking and marked obesity) and non-modifiable factors (having brown eyes, myopia and high pulse pressure). Vitamin supplement use was not related to cataract. Conclusion These data add to the body of evidence suggesting that eating foods that are rich in a variety of vitamins and minerals, may contribute to postponing the occurrence of the most common type of cataract in the US. PMID:20547952
Inheritance of yeast nuclear pore complexes requires the Nsp1p subcomplex
Makio, Tadashi; Lapetina, Diego L.
2013-01-01
In the yeast Saccharomyces cerevisiae, organelles and macromolecular complexes are delivered from the mother to the emerging daughter during cell division, thereby ensuring progeny viability. Here, we have shown that during mitosis nuclear pore complexes (NPCs) in the mother nucleus are actively delivered through the bud neck and into the daughter cell concomitantly with the nuclear envelope. Furthermore, we show that NPC movement into the daughter cell requires members of an NPC subcomplex containing Nsp1p and its interacting partners. NPCs lacking these nucleoporins (Nups) were blocked from entry into the daughter by a putative barrier at the bud neck. This selection process could be observed within individual cells such that NPCs containing Nup82p (an Nsp1p-interacting Nup) were transferred to the daughter cells while functionally compromised NPCs lacking Nup82p were retained in the mother. This mechanism is proposed to facilitate the inheritance of functional NPCs by daughter cells. PMID:24165935
Peoples, R J; Cisco, M J; Kaplan, P; Francke, U
1998-01-01
We have identified a novel gene (WBSCR9) within the common Williams-Beuren syndrome (WBS) deletion by interspecies sequence conservation. The WBSCR9 gene encodes a roughly 7-kb transcript with an open reading frame of 1483 amino acids and a predicted protein product size of 170.8 kDa. WBSCR9 is comprised of at least 20 exons extending over 60 kb. The transcript is expressed ubiquitously throughout development and is subject to alternative splicing. Functional motifs identified by sequence homology searches include a bromodomain; a PHD, or C4HC3, finger; several putative nuclear localization signals; four nuclear receptor binding motifs; a polyglutamate stretch and two PEST sequences. Bromodomains, PHD motifs and nuclear receptor binding motifs are cardinal features of proteins that are involved in chromatin remodeling and modulation of transcription. Haploinsufficiency for WBSCR9 gene products may contribute to the complex phenotype of WBS by interacting with tissue-specific regulatory factors during development.
Three-dimensional visualization of gammaherpesvirus life cycle in host cells by electron tomography.
Peng, Li; Ryazantsev, Sergey; Sun, Ren; Zhou, Z Hong
2010-01-13
Gammaherpesviruses are etiologically associated with human tumors. A three-dimensional (3D) examination of their life cycle in the host is lacking, significantly limiting our understanding of the structural and molecular basis of virus-host interactions. Here, we report the first 3D visualization of key stages of the murine gammaherpesvirus 68 life cycle in NIH 3T3 cells, including viral attachment, entry, assembly, and egress, by dual-axis electron tomography. In particular, we revealed the transient processes of incoming capsids injecting viral DNA through nuclear pore complexes and nascent DNA being packaged into progeny capsids in vivo as a spool coaxial with the putative portal vertex. We discovered that intranuclear invagination of both nuclear membranes is involved in nuclear egress of herpesvirus capsids. Taken together, our results provide the structural basis for a detailed mechanistic description of gammaherpesvirus life cycle and also demonstrate the advantage of electron tomography in dissecting complex cellular processes of viral infection.
Kao, L R; Megraw, T L; Chae, C B
1993-06-15
The yeast mitochondrial histone protein HM is required for maintenance of the mitochondrial genome, and disruption of the gene encoding HM (HIM1/ABF2) results in formation of a respiration-deficient petite mutant phenotype. HM contains two homologous regions, which share sequence similarity with the eukaryotic nuclear nonhistone protein, HMG-1. Experiments with various deletion mutants of HM show that a single HMG domain of HM is functional and can restore respiration competency to cells that lack HM protein (him1 mutant cells). The gene encoding the putative yeast nuclear HMG-1 homolog, the NHP6A protein, can functionally complement the him1 mutation. These results suggest that the HMG domain is the basic unit for the function of HM in mitochondria and that the function of HMG-1 proteins in the nucleus and HM in the mitochondrion may be equivalent.
Lamm, Christian E; Link, Katrin; Wagner, Sabrina; Milbradt, Jens; Marschall, Manfred; Sonnewald, Uwe
2016-03-10
In all eukaryotic cells, the nucleus forms a prominent cellular compartment containing the cell's nuclear genome. Although structurally similar, animal and plant nuclei differ substantially in details of their architecture. One example is the nuclear lamina, a layer of tightly interconnected filament proteins (lamins) underlying the nuclear envelope of metazoans. So far no orthologous lamin genes could be detected in plant genomes and putative lamin-like proteins are only poorly described in plants. To probe for potentially conserved features of metazoan and plant nuclear envelopes, we ectopically expressed the core nuclear egress proteins of human cytomegalovirus pUL50 and pUL53 in plant cells. pUL50 localizes to the inner envelope of metazoan nuclei and recruits the nuclear localized pUL53 to it, forming heterodimers. Upon expression in plant cells, a very similar localization pattern of both proteins could be determined. Notably, pUL50 is specifically targeted to the plant nuclear envelope in a rim-like fashion, a location to which coexpressed pUL53 becomes strictly corecruited from its initial nucleoplasmic distribution. Using pUL50 as bait in a yeast two-hybrid screening, the cytoplasmic re-initiation supporting protein RISP could be identified. Interaction of pUL50 and RISP could be confirmed by coexpression and coimmunoprecipitation in mammalian cells and by confocal laser scanning microscopy in plant cells, demonstrating partial pUL50-RISP colocalization in areas of the nuclear rim and other intracellular compartments. Thus, our study provides strong evidence for conserved structural features of plant and metazoan nuclear envelops and identifies RISP as a potential pUL50-interacting plant protein.
Using a Genetic Algorithm to Design Nuclear Electric Spacecraft
NASA Technical Reports Server (NTRS)
Pannell, William P.
2003-01-01
The basic approach to to design nuclear electric spacecraft is to generate a group of candidate designs, see how "fit" the design are, and carry best design forward to the next generation. Some designs eliminated, some randomly modified and carried forward.
Heese-Peck, A; Cole, R N; Borkhsenious, O N; Hart, G W; Raikhel, N V
1995-01-01
Only a few nuclear pore complex (NPC) proteins, mainly in vertebrates and yeast but none in plants, have been well characterized. As an initial step to identify plant NPC proteins, we examined whether NPC proteins from tobacco are modified by N-acetylglucosamine (GlcNAc). Using wheat germ agglutinin, a lectin that binds specifically to GlcNAc in plants, specific labeling was often found associated with or adjacent to NPCs. Nuclear proteins containing GlcNAc can be partially extracted by 0.5 M salt, as shown by a wheat germ agglutinin blot assay, and at least eight extracted proteins were modified by terminal GlcNAc, as determined by in vitro galactosyltransferase assays. Sugar analysis indicated that the plant glycans with terminal GlcNAc differ from the single O-linked GlcNAc of vertebrate NPC proteins in that they consist of oligosaccharides that are larger in size than five GlcNAc residues. Most of these appear to be bound to proteins via a hydroxyl group. This novel oligosaccharide modification may convey properties to the plant NPC that are different from those of vertebrate NPCs. PMID:8589629
Human stanniocalcin-1 interacts with nuclear and cytoplasmic proteins and acts as a SUMO E3 ligase.
dos Santos, Marcos Tadeu; Trindade, Daniel Maragno; Gonçalves, Kaliandra de Almeida; Bressan, Gustavo Costa; Anastassopoulos, Filipe; Yunes, José Andres; Kobarg, Jörg
2011-01-01
Human stanniocalcin-1 (STC1) is a glycoprotein that has been implicated in different physiological process, including angiogenesis, apoptosis and carcinogenesis. Here we identified STC1 as a putative molecular marker for the leukemic bone marrow microenvironment and identified new interacting protein partners for STC1. Seven selected interactions retrieved from yeast two-hybrid screens were confirmed by GST-pull down assays in vitro. The N-terminal region was mapped to be the region that mediates the interaction with cytoplasmic, mitochondrial and nuclear proteins. STC1 interacts with SUMO-1 and several proteins that have been shown to be SUMOylated and localized to SUMOylation related nuclear bodies. Although STC1 interacts with SUMO-1 and has a high theoretical prediction score for a SUMOylation site, endogenous co-immunoprecipitation and in vitro SUMOylation assays with the purified recombinant protein could not detect STC1 SUMOylation. However, when we tested STC1 for SUMO E3 ligase activity, we found in an in vitro assay, that it significantly increases the SUMOylation of two other proteins. Confocal microscopic subcellular localization studies using both transfected cells and specific antibodies for endogenous STC1 revealed a cytoplasmic and nuclear deposition, the latter in the form of some specific dot-like substructure resembling SUMOylation related nuclear bodies. Together, these findings suggest a new role for STC1 in SUMOylation pathways, in nuclear bodies.
From Genomes to Protein Models and Back
NASA Astrophysics Data System (ADS)
Tramontano, Anna; Giorgetti, Alejandro; Orsini, Massimiliano; Raimondo, Domenico
2007-12-01
The alternative splicing mechanism allows genes to generate more than one product. When the splicing events occur within protein coding regions they can modify the biological function of the protein. Alternative splicing has been suggested as one way for explaining the discrepancy between the number of human genes and functional complexity. We analysed the putative structure of the alternatively spliced gene products annotated in the ENCODE pilot project and discovered that many of the potential alternative gene products will be unlikely to produce stable functional proteins.
High unexpected genetic diversity of a narrow endemic terrestrial mollusc
Madeira, Pedro M.; Chefaoui, Rosa M.; Cunha, Regina L.; Moreira, Francisco; Dias, Susana; Calado, Gonçalo
2017-01-01
The Iberian Peninsula has an extensive record of species displaying strong genetic structure as a result of their survival in isolated pockets throughout the Pleistocene ice ages. We used mitochondrial and nuclear sequence data to analyze phylogeographic patterns in endemic land snails from a valley of central Portugal (Vale da Couda), putatively assigned to Candidula coudensis, that show an exceptionally narrow distributional range. The genetic survey presented here shows the existence of five main mitochondrial lineages in Vale da Couda that do not cluster together suggesting independent evolutionary histories. Our results also indicate a departure from the expectation that species with restricted distributions have low genetic variability. The putative past and contemporary models of geographic distribution of Vale da Couda lineages are compatible with a scenario of species co-existence in more southern locations during the last glacial maximum (LGM) followed by a post-LGM northern dispersal tracking the species optimal thermal, humidity and soil physical conditions. PMID:28321363
Wise, C A; Chiang, L C; Paznekas, W A; Sharma, M; Musy, M M; Ashley, J A; Lovett, M; Jabs, E W
1997-04-01
Treacher Collins Syndrome (TCS) is the most common of the human mandibulofacial dysostosis disorders. Recently, a partial TCOF1 cDNA was identified and shown to contain mutations in TCS families. Here we present the entire exon/intron genomic structure and the complete coding sequence of TCOF1. TCOF1 encodes a low complexity protein of 1,411 amino acids, whose predicted protein structure reveals repeated motifs that mirror the organization of its exons. These motifs are shared with nucleolar trafficking proteins in other species and are predicted to be highly phosphorylated by casein kinase. Consistent with this, the full-length TCOF1 protein sequence also contains putative nuclear and nucleolar localization signals. Throughout the open reading frame, we detected an additional eight mutations in TCS families and several polymorphisms. We postulate that TCS results from defects in a nucleolar trafficking protein that is critically required during human craniofacial development.
Wise, Carol A.; Chiang, Lydia C.; Paznekas, William A.; Sharma, Mridula; Musy, Maurice M.; Ashley, Jennifer A.; Lovett, Michael; Jabs, Ethylin W.
1997-01-01
Treacher Collins Syndrome (TCS) is the most common of the human mandibulofacial dysostosis disorders. Recently, a partial TCOF1 cDNA was identified and shown to contain mutations in TCS families. Here we present the entire exon/intron genomic structure and the complete coding sequence of TCOF1. TCOF1 encodes a low complexity protein of 1,411 amino acids, whose predicted protein structure reveals repeated motifs that mirror the organization of its exons. These motifs are shared with nucleolar trafficking proteins in other species and are predicted to be highly phosphorylated by casein kinase. Consistent with this, the full-length TCOF1 protein sequence also contains putative nuclear and nucleolar localization signals. Throughout the open reading frame, we detected an additional eight mutations in TCS families and several polymorphisms. We postulate that TCS results from defects in a nucleolar trafficking protein that is critically required during human craniofacial development. PMID:9096354
Nakamoto, Masashi; Fujii, Takuto; Matsutomo, Toshiaki; Kodera, Yukihiro
2018-03-21
We analyzed aged garlic extract (AGE) to understand its complex sulfur chemistry using post-column high-performance liquid chromatography with an iodoplatinate reagent and liquid chromatography high resolution mass spectrometry (LC-MS). We observed unidentified peaks of putative sulfur compounds. Three compounds were isolated and identified as γ-glutamyl-γ-glutamyl- S-methylcysteine, γ-glutamyl-γ-glutamyl- S-allylcysteine (GGSAC) and γ-glutamyl-γ-glutamyl- S-1-propenyl-cysteine (GGS1PC) by nuclear magnetic resonance and LC-MS analysis based on comparisons with chemically synthesized reference compounds. GGSAC and GGS1PC were novel compounds. Trace amounts of these compounds were detected in raw garlic, but the contents of these compounds increased during the aging process. Production of these compounds was inhibited using a γ-glutamyl transpeptidase (GGT) inhibitor in the model reaction mixtures. These findings suggest that γ-glutamyl tripeptides in AGE are produced by GGT during the aging process.
Farnsworth, Aaron; Wisner, Todd W; Webb, Michael; Roller, Richard; Cohen, Gary; Eisenberg, Roselyn; Johnson, David C
2007-06-12
Herpesviruses must traverse the nuclear envelope to gain access to the cytoplasm and, ultimately, to exit cells. It is believed that herpesvirus nucleocapsids enter the perinuclear space by budding through the inner nuclear membrane (NM). To reach the cytoplasm these enveloped particles must fuse with the outer NM and the unenveloped capsids then acquire a second envelope in the trans-Golgi network. Little is known about the process by which herpesviruses virions fuse with the outer NM. Here we show that a herpes simplex virus (HSV) mutant lacking both the two putative fusion glycoproteins gB and gH failed to cross the nuclear envelope. Enveloped virions accumulated in the perinuclear space or in membrane vesicles that bulged into the nucleoplasm (herniations). By contrast, mutants lacking just gB or gH showed only minor or no defects in nuclear egress. We concluded that either HSV gB or gH can promote fusion between the virion envelope and the outer NM. It is noteworthy that fusion associated with HSV entry requires the cooperative action of both gB and gH, suggesting that the two types of fusion (egress versus entry) are dissimilar processes.
Holden, Jennifer M.; Koreny, Ludek; Obado, Samson; Ratushny, Alexander V.; Chen, Wei-Ming; Chiang, Jung-Hsien; Kelly, Steven; Chait, Brian T.; Aitchison, John D.; Rout, Michael P.; Field, Mark C.
2014-01-01
The nuclear pore complex (NPC) has dual roles in nucleocytoplasmic transport and chromatin organization. In many eukaryotes the coiled-coil Mlp/Tpr proteins of the NPC nuclear basket have specific functions in interactions with chromatin and defining specialized regions of active transcription, whereas Mlp2 associates with the mitotic spindle/NPC in a cell cycle–dependent manner. We previously identified two putative Mlp-related proteins in African trypanosomes, TbNup110 and TbNup92, the latter of which associates with the spindle. We now provide evidence for independent ancestry for TbNup92/TbNup110 and Mlp/Tpr proteins. However, TbNup92 is required for correct chromosome segregation, with knockout cells exhibiting microaneuploidy and lowered fidelity of telomere segregation. Further, TbNup92 is intimately associated with the mitotic spindle and spindle anchor site but apparently has minimal roles in control of gene transcription, indicating that TbNup92 lacks major barrier activity. TbNup92 therefore acts as a functional analogue of Mlp/Tpr proteins, and, together with the lamina analogue NUP-1, represents a cohort of novel proteins operating at the nuclear periphery of trypanosomes, uncovering complex evolutionary trajectories for the NPC and nuclear lamina. PMID:24600046
Cyclophilin B enhances HIV-1 infection
DOE Office of Scientific and Technical Information (OSTI.GOV)
DeBoer, Jason; Madson, Christian J.; Belshan, Michael, E-mail: michaelbelshan@creighton.edu
Cyclophilin B (CypB) is a member of the immunophilin family and intracellular chaperone. It predominantly localizes to the ER, but also contains a nuclear localization signal and is secreted from cells. CypB has been shown to interact with the Gag protein of human immunodeficiency type 1 (HIV-1). Several proteomic and genetic studies identified it as a potential factor involved in HIV replication. Herein, we show that over-expression of CypB enhances HIV infection by increasing nuclear import of viral DNA. This enhancement was unaffected by cyclosporine treatment and requires the N-terminus of the protein. The N-terminus contains an ER leader sequence,more » putative nuclear localization signal, and is required for secretion. Deletion of the N-terminus resulted in mislocalization from the ER and suppression of HIV infection. Passive transfer experiments showed that secreted CypB did not impact HIV infection. Combined, these experiments show that intracellular CypB modulates a pathway of HIV nuclear import. - Highlights: • CypB has been identified in several proteomic studies of HIV-1 infection. • CypB expression is upregulated in activated and infected T-cells. • Over-expression of CypB enhances HIV nuclear import and infection. • The N-terminus of CypB is necessary for these effects.« less
Germline Genetic Modification and Identity: the Mitochondrial and Nuclear Genomes
Scott, Rosamund; Wilkinson, Stephen
2017-01-01
Abstract In a legal ‘first’, the UK removed a prohibition against modifying embryos in human reproduction, to enable mitochondrial replacement techniques (MRTs), a move the Government distanced from ‘germline genetic modification’, which it aligned with modifying the nuclear genome. This paper (1) analyzes the uses and meanings of this term in UK/US legal and policy debates; and (2) evaluates related ethical concerns about identity. It shows that, with respect to identity, MRTs and nuclear genome editing techniques such as CRISPR/Cas-9 (now a policy topic), are not as different as has been supposed. While it does not follow that the two should be treated exactly alike, one of the central reasons offered for treating MRTs more permissively than nuclear genetic modification, and for not regarding MRTs as ‘germline genetic modification’, is thereby in doubt. Identity cannot, by itself, do the work thus far assigned to it, explicitly or otherwise, in law and policy. PMID:29670305
NASA Astrophysics Data System (ADS)
Zaman, D. M. S.; Amina, M.; Dip, P. R.; Mamun, A. A.
2017-11-01
The basic properties of planar and non-planar (spherical and cylindrical) nucleus-acoustic (NA) shock structures (SSs) in a strongly coupled self-gravitating degenerate quantum plasma system (containing strongly coupled non-relativistically degenerate heavy nuclear species, weakly coupled non-relativistically degenerate light nuclear species, and inertialess non-/ultra-relativistically degenerate electrons) have been investigated. The generalized quantum hydrodynamic model and the reductive perturbation method have been used to derive the modified Burgers equation. It is shown that the strong correlation among heavy nuclear species acts as the source of dissipation and is responsible for the formation of the NA SSs with positive (negative) electrostatic (self-gravitational) potential. It is also observed that the effects of non-/ultra-relativistically degenerate electron pressure, dynamics of non-relativistically degenerate light nuclear species, spherical geometry, etc., significantly modify the basic features of the NA SSs. The applications of our results in astrophysical compact objects like white dwarfs and neutron stars are briefly discussed.
Boehn, Susanne N.E.; Spahn, Sonja; Neudecker, Sabine; Keppler, Andrea; Bihoreau, Marie-Thérèse; Kränzlin, Bettina; Pandey, Priyanka; Hoffmann, Sigrid C.; Li, Li; Torres, Vicente E.; Gröne, Hermann-Josef; Gretz, Norbert
2013-01-01
Background Autosomal dominant polycystic kidney disease (ADPKD) is one of the most common human inherited diseases. Modifier genes seem to modulate the disease progression and might therefore be promising drug targets. Although a number of modifier loci have been already identified, no modifier gene has been proven to be a real modifier yet. Methods Gene expression profiling of two substrains of the Han:SPRD rat, namely PKD/Mhm and PKD/US, both harboring the same mutation, was conducted in 36-day-old animals. Catechol-O-methyltransferase (Comt) was identified as a potential modifier gene. A 3-month treatment with tolcapone, a selective inhibitor of Comt, was carried out in PKD/Mhm and PKD/US (cy/+) animals. Results Comt is localized within a known modifier locus of PKD (MOP2). The enzyme encoding gene was found upregulated in the more severely affected PKD/Mhm substrain and was hence presumed to be a putative modifier gene of PKD. The treatment with tolcapone markedly attenuated the loss of renal function, inhibited renal enlargement, shifted the size distribution of renal cysts and retarded cell proliferation, apoptosis, inflammation and fibrosis development in affected (cy/+) male and female PKD/Mhm and PKD/US rats. Conclusions Comt has been confirmed to be the first reported modifier gene for PKD and tolcapone offers a promising drug for treating PKD. PMID:23543593
Psychometric Characteristics of the Modified World Affairs Questionnaire.
ERIC Educational Resources Information Center
Mayton, Daniel M., II
1988-01-01
Subjected Modified World Affairs Questionnaire (MWAQ) to comparable common factor analysis which identified five factors: civil defense, escalation, nuclear war outcome, probability/worry, and patriotic. Alpha coefficients and test-retest reliability were determined to be adequate for the first four subscales. Acceptable discriminant validity and…
Genome-wide screen uncovers novel pathways for tRNA processing and nuclear-cytoplasmic dynamics.
Wu, Jingyan; Bao, Alicia; Chatterjee, Kunal; Wan, Yao; Hopper, Anita K
2015-12-15
Transfer ribonucleic acids (tRNAs) are essential for protein synthesis. However, key gene products involved in tRNA biogenesis and subcellular movement remain to be discovered. We conducted the first comprehensive unbiased analysis of the role of nearly an entire proteome in tRNA biology and describe 162 novel and 12 previously known Saccharomyces cerevisiae gene products that function in tRNA processing, turnover, and subcellular movement. tRNA nuclear export is of particular interest because it is essential, but the known tRNA exporters (Los1 [exportin-t] and Msn5 [exportin-5]) are unessential. We report that mutations of CRM1 (Exportin-1), MEX67/MTR2 (TAP/p15), and five nucleoporins cause accumulation of unspliced tRNA, a hallmark of defective tRNA nuclear export. CRM1 mutation genetically interacts with los1Δ and causes altered tRNA nuclear-cytoplasmic distribution. The data implicate roles for the protein and mRNA nuclear export machineries in tRNA nuclear export. Mutations of genes encoding actin cytoskeleton components and mitochondrial outer membrane proteins also cause accumulation of unspliced tRNA, likely due to defective splicing on mitochondria. Additional gene products, such as chromatin modification enzymes, have unanticipated effects on pre-tRNA end processing. Thus, this genome-wide screen uncovered putative novel pathways for tRNA nuclear export and extensive links between tRNA biology and other aspects of cell physiology. © 2015 Wu et al.; Published by Cold Spring Harbor Laboratory Press.
Oshima, Naohiro; Masada, Sayaka; Suzuki, Ryuta; Yagi, Kanae; Matsufuji, Hiroshi; Suenaga, Emi; Takahashi, Yutaka; Yahagi, Tadahiro; Watanabe, Masato; Yahara, Shoji; Iida, Osamu; Kawahara, Nobuo; Maruyama, Takuro; Goda, Yukihiro; Hakamatsuka, Takashi
2016-01-01
Agnus Castus Fruit is defined in the European Pharmacopoeia as the dried ripe fruit of Vitex agnus-castus. In Europe it is used as a medicine targeting premenstrual syndrome and climacteric disorder. In Japan, Agnus Castus Fruit is becoming popular as a raw material for over-the-counter drugs and health food products, though its congenic species, Vitex rotundifolia and Vitex trifolia, have been used as Shrub Chaste Tree Fruit in traditional medicines. Therefore, it is important to discriminate these Vitex plants from the viewpoint of regulatory science. Here we tried to identify putative marker compounds that distinguish between Agnus Castus Fruit and Shrub Chaste Tree Fruit. We analyzed extracts of each crude drug by liquid chromatography-mass spectrometry, and performed differential analysis by comparison of each chromatogram to find one or more peaks characteristic of Agnus Castus Fruit. A peak was isolated and identified as an equilibrium mixture of new compounds named chastol (1) and epichastol (1a). The planar structures of 1 and 1a were determined spectroscopically. Their relative configurations were revealed by nuclear Overhauser effect spectroscopy and differential nuclear Overhauser effect-NMR data. Since avoiding contamination from closely related species is needed for the quality control of natural pharmaceuticals, this information will be valuable to establish a method for the quality control of both, Agnus Castus Fruit and Shrub Chaste Tree Fruit products. Georg Thieme Verlag KG Stuttgart · New York.
Vought, Valarie E.; Ohmachi, Mitsue; Lee, Min-Ho; Maine, Eleanor M.
2005-01-01
Caenorhabditis elegans EGO-1, a putative cellular RNA-directed RNA polymerase, promotes several aspects of germline development, including proliferation, meiosis, and gametogenesis, and ensures a robust response to RNA interference. In C. elegans, GLP-1/Notch signaling from the somatic gonad maintains a population of proliferating germ cells, while entry of germ cells into meiosis is triggered by the GLD-1 and GLD-2 pathways. GLP-1 signaling prevents germ cells from entering meiosis by inhibiting GLD-1 and GLD-2 activity. We originally identified the ego-1 gene on the basis of a genetic interaction with glp-1. Here, we investigate the role of ego-1 in germline proliferation. Our data indicate that EGO-1 does not positively regulate GLP-1 protein levels or GLP-1 signaling activity. Moreover, GLP-1 signaling does not positively regulate EGO-1 activity. EGO-1 does not inhibit expression of GLD-1 protein in the distal germline. Instead, EGO-1 acts in parallel with GLP-1 signaling to influence the proliferation vs. meiosis fate choice. Moreover, EGO-1 and GLD-1 act in parallel to ensure germline health. Finally, the size and distribution of nuclear pore complexes and perinuclear P granules are altered in the absence of EGO-1, effects that disrupt germ cell biology per se and probably limit germline growth. PMID:15911573
Correll, Robert N; Makarewich, Catherine A; Zhang, Hongyu; Zhang, Chen; Sargent, Michelle A; York, Allen J; Berretta, Remus M; Chen, Xiongwen; Houser, Steven R; Molkentin, Jeffery D
2017-06-01
L-type Ca2+ channels (LTCCs) in adult cardiomyocytes are localized to t-tubules where they initiate excitation-contraction coupling. Our recent work has shown that a subpopulation of LTCCs found at the surface sarcolemma in caveolae of adult feline cardiomyocytes can also generate a Ca2+ microdomain that activates nuclear factor of activated T-cells signaling and cardiac hypertrophy, although the relevance of this paradigm to hypertrophy regulation in vivo has not been examined. Here we generated heart-specific transgenic mice with a putative caveolae-targeted LTCC activator protein that was ineffective in initiating or enhancing cardiac hypertrophy in vivo. We also generated transgenic mice with cardiac-specific overexpression of a putative caveolae-targeted inhibitor of LTCCs, and while this protein inhibited caveolae-localized LTCCs without effects on global Ca2+ handling, it similarly had no effect on cardiac hypertrophy in vivo. Cardiac hypertrophy was elicited by pressure overload for 2 or 12 weeks or with neurohumoral agonist infusion. Caveolae-specific LTCC activator or inhibitor transgenic mice showed no greater change in nuclear factor of activated T-cells activity after 2 weeks of pressure overload stimulation compared with control mice. Our results indicate that LTCCs in the caveolae microdomain do not affect cardiac function and are not necessary for the regulation of hypertrophic signaling in the adult mouse heart. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions, please email: journals.permissions@oup.com.
Malecki, Marek; Malecki, Bianca
2012-01-01
In health and disease, biomolecules, which are involved in gene expression, recombination, or reprogramming have to traffic through the nucleoplasm, between nuclear pore complexes (NPCs) and genomic DNA (gDNA). This trafficking is guided by the recently revealed nuclear routing networks (NRNs). In this study, we aimed to investigate, if the NRNs have established associations with the genomic DNA in situ and if the NRNs have capabilities to bind the DNA de novo. Moreover, we aimed to study further, if nucleoplasmic trafficking of the histones, rRNA, and transgenes’ vectors, between the NPCs and gDNA, is guided by the NRNs. We used Xenopus laevis oocytes as the model system. We engineered the transgenes’ DNA vectors equipped with the SV40 LTA nuclear localization signals (NLS) and/or HIV Rev nuclear export signals (NES). We purified histones, 5S rRNA, and gDNA. We rendered all these molecules superparamagnetic and fluorescent for detection with nuclear magnetic resonance (NMR), total reflection x-ray fluorescence (TXRF), energy dispersive x-ray spectroscopy (EDXS), and electron energy loss spectroscopy (EELS). The NRNs span between the NPCs and genomic DNA. They form firm bonds with the gDNA in situ. After complete digestion of the nucleic acids with the RNases and DNases, the newly added DNA - modified with the dNTP analogs, bonds firmly to the NRNs. Moreover, the NRNs guide the trafficking of the DNA transgenes’ vectors - modified with the SV40 LTA NLS, following their import into the nuclei through the NPCs. The pathway is identical to that of histones. The NRNs also guide the trafficking of the DNA transgenes’ vectors, modified with the HIV Rev NES, to the NPCs, followed by their export out of the nuclei. Ribosomal RNAs follow the same pathway. To summarize, the NRNs are the structures connecting the NPCs and the gDNA. They guide the trafficking of the biomolecules between the NPCs and the gDNA. PMID:23275893
The roles of ubiquitin modifying enzymes in neoplastic disease.
Kumari, Nishi; Jaynes, Patrick William; Saei, Azad; Iyengar, Prasanna Vasudevan; Richard, John Lalith Charles; Eichhorn, Pieter Johan Adam
2017-12-01
The initial experiments performed by Rose, Hershko, and Ciechanover describing the identification of a specific degradation signal in short-lived proteins paved the way to the discovery of the ubiquitin mediated regulation of numerous physiological functions required for cellular homeostasis. Since their discovery of ubiquitin and ubiquitin function over 30years ago it has become wholly apparent that ubiquitin and their respective ubiquitin modifying enzymes are key players in tumorigenesis. The human genome encodes approximately 600 putative E3 ligases and 80 deubiquitinating enzymes and in the majority of cases these enzymes exhibit specificity in sustaining either pro-tumorigenic or tumour repressive responses. In this review, we highlight the known oncogenic and tumour suppressive effects of ubiquitin modifying enzymes in cancer relevant pathways with specific focus on PI3K, MAPK, TGFβ, WNT, and YAP pathways. Moreover, we discuss the capacity of targeting DUBs as a novel anticancer therapeutic strategy. Copyright © 2017 Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Abrams, Charles C.; Chapman, Dave A.G.; Silk, Rhiannon
2008-05-10
The African swine fever virus A238L protein inhibits calcineurin phosphatase activity and activation of NF-{kappa}B and p300 co-activator. An 82 amino acid domain containing residues 157 to 238 at the C-terminus of A238L was expressed in E. coli and purified. This purified A238L fragment acted as a potent inhibitor of calcineurin phosphatase in vitro with an IC{sub 50} of approximately 70 nM. Two putative nuclear localisation signals were identified between residues 80 to 86 (NLS-1) and between residues 203 to 207 overlapping with the N-terminus of the calcineurin docking motif (NLS-2). Mutation of these motifs independently did not reduce nuclearmore » localisation compared to the wild type A238L protein, whereas mutation of both motifs significantly reduced nuclear localisation of A238L. Mutation of the calcineurin docking motif resulted in a dramatic increase in the nuclear localisation of A238L provided an intact NLS was present. We propose that binding of calcineurin to A238L masks NLS-2 contributing to the cytoplasmic retention of A238L.« less
Chen, Shun; Liu, Peng; He, Yu; Yang, Chao; Wang, Mingshu; Jia, Renyong; Zhu, Dekang; Liu, Mafeng; Yang, Qiao; Wu, Ying; Cheng, Anchun
2018-06-01
goose parvovirus (GPV) belongs to the Dependoparvovirus genus in Parvovirinae subfamily within Parvoviridae family, is the etiological agent of Derzsy's disease. Nuclear localization signal (NLS) is important for parvovirus lifecycle in the delivery of genomes and the structural protein of progeny virus into the nucleus. Here, NLS was first identified in GPV. By using the PSORT II program, a basic region (BR, 160YPVVKKPKLTEE171) in the N-terminus of VP1 was found, which predicted as putative NLS motif of goose parvovirus capsid. The GPV BR could transfer both small reporter proteins (EGFP) and large reporter protein (β-galactosidase) into the nucleus by Immunofluorescence assay. Furthermore, the K164A, or K165A, or K167A substitutions mutation of GPV VP1 did abolish its nuclear localization, suggesting that the 164 K, 165 K and 167 K residues in the 160YPVVKKPKLTEE171 are required for its for nuclear import. Our finding may help us to gain a better understand of GPV lifecycle. Copyright © 2018 Elsevier Inc. All rights reserved.
Durand, Jean-Dominique; Borsa, Philippe
2015-04-01
The low level of morphometric variability and the poor phylogenetic information borne by the morpho-anatomical characters used thus far in the systematics of grey mullets (Mugilidae) emphasize the utility of molecular systematics in this family. A recent mitochondrial phylogeny of grey mullets has uncovered multiple deep lineages within several species, flagging putative cryptic species. Here, we considered that several of the deeply divergent lineages represent separate species based on either the tree topology, independent data from nuclear markers, geographic distributions, or a combination of the foregoing. By analogy with these well-documented cases, we considered other deep lineages in seven genera we focused on to represent putative cryptic species. Up to two cryptic species were thus potentially detected in the genus Chelon, three in Crenimugil (including two within the single Crenimugil seheli), two in Dajaus, one in Ellochelon, 16 in Mugil (including 13 within the single M. cephalus), two in Osteomugil, and 10 in Planiliza. Wherever possible, we kept the current species epithets to designate those lineages that unambiguously correspond to the type material, based on type locality, and we assigned arbitrary letters (sp. A, B, etc.) to the other lineages. We present a molecular diagnosis for 24 of the species analysed in this work, as well as for 25 putative cryptic species. Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.
2012-01-01
Background Galeommatoidea is a superfamily of bivalves that exhibits remarkably diverse lifestyles. Many members of this group live attached to the body surface or inside the burrows of other marine invertebrates, including crustaceans, holothurians, echinoids, cnidarians, sipunculans and echiurans. These symbiotic species exhibit high host specificity, commensal interactions with hosts, and extreme morphological and behavioral adaptations to symbiotic life. Host specialization to various animal groups has likely played an important role in the evolution and diversification of this bivalve group. However, the evolutionary pathway that led to their ecological diversity is not well understood, in part because of their reduced and/or highly modified morphologies that have confounded traditional taxonomy. This study elucidates the taxonomy of the Galeommatoidea and their evolutionary history of symbiotic lifestyle based on a molecular phylogenic analysis of 33 galeommatoidean and five putative galeommatoidean species belonging to 27 genera and three families using two nuclear ribosomal genes (18S and 28S ribosomal DNA) and a nuclear (histone H3) and mitochondrial (cytochrome oxidase subunit I) protein-coding genes. Results Molecular phylogeny recovered six well-supported major clades within Galeommatoidea. Symbiotic species were found in all major clades, whereas free-living species were grouped into two major clades. Species symbiotic with crustaceans, holothurians, sipunculans, and echiurans were each found in multiple major clades, suggesting that host specialization to these animal groups occurred repeatedly in Galeommatoidea. Conclusions Our results suggest that the evolutionary history of host association in Galeommatoidea has been remarkably dynamic, involving frequent host switches between different animal phyla. Such an unusual pattern of dynamic host switching is considered to have resulted from their commensalistic lifestyle, in which they maintain filter-feeding habits even in symbiotic habitats. The results of the molecular phylogenetic analysis did not correspond with the current taxonomic circumscription. Galeommatidae and Lasaeidae were polyphyletic, and Basterotia, which is traditionally assigned to Cyamioidea, formed a monophyletic clade within Galeommatoidea. PMID:22954375
Determination of Surface-Exposed, Functional Domains of Gonococcal Transferrin-Binding Protein A
Yost-Daljev, Mary Kate; Cornelissen, Cynthia Nau
2004-01-01
The gonococcal transferrin receptor is composed of two distinct proteins, TbpA and TbpB. TbpA is a member of the TonB-dependent family of integral outer membrane transporters, while TbpB is lipid modified and thought to be peripherally surface exposed. We previously proposed a hypothetical topology model for gonococcal TbpA that was based upon computer predictions and similarity with other TonB-dependent transporters for which crystal structures have been determined. In the present study, the hemagglutinin epitope was inserted into TbpA to probe the surface topology of this protein and secondarily to test the functional impacts of site-specific mutagenesis. Twelve epitope insertion mutants were constructed, five of which allowed us to confirm the surface exposure of loops 2, 3, 5, 7, and 10. In contrast to the predictions set forth by the hypothetical model, insertion into the plug region resulted in an epitope that was surface accessible, while epitope insertions into two putative loops (9 and 11) were not surface accessible. Insertions into putative loop 3 and β strand 9 abolished transferrin binding and utilization, and the plug insertion mutant exhibited decreased transferrin-binding affinity concomitant with an inability to utilize it. Insertion into putative β strand 16 generated a mutant that was able to bind transferrin normally but that was unable to mediate utilization. Mutants with insertions into putative loops 2, 9, and 11 maintained wild-type binding affinity but could utilize only transferrin in the presence of TbpB. This is the first demonstration of the ability of TbpB to compensate for a mutation in TbpA. PMID:14977987
Conner, Anthony J; Glare, Travis R; Nap, Jan-Peter
2003-01-01
Despite numerous future promises, there is a multitude of concerns about the impact of GM crops on the environment. Key issues in the environmental assessment of GM crops are putative invasiveness, vertical or horizontal gene flow, other ecological impacts, effects on biodiversity and the impact of presence of GM material in other products. These are all highly interdisciplinary and complex issues. A crucial component for a proper assessment is defining the appropriate baseline for comparison and decision. For GM crops, the best and most appropriately defined reference point is the impact of plants developed by traditional breeding. The latter is an integral and accepted part of agriculture. In many instances, the putative impacts identified for GM crops are very similar to the impacts of new cultivars derived from traditional breeding. When assessing GM crops relative to existing cultivars, the increased knowledge base underpinning the development of GM crops will provide greater confidence in the assurances plant science can give on the risks of releasing such crops.
Tissue Specific and Hormonal Regulation of Gene Expression
1997-08-01
interference assays were performed. These assays identify DNA bases that, when modified, interfere with the binding of the nuclear factor to the hCRH promoter...thymidine residues. The DNA bases that when modified affected the binding of the protein are noted with arrows, and their location in the hCRH...indicated. B. Methylation interference. The fragments were partially methylated using dimethyl sulfate. The DNA bases that when modified affected the
Federal Register 2010, 2011, 2012, 2013, 2014
2010-11-16
... NUCLEAR REGULATORY COMMISSION [Docket Nos (Redacted), License Nos (Redacted), EA (Redacted); NRC- 2010-0351] In the Matter of All Power Reactor Licensees and Research Reactor Licensees Who Transport Spent Nuclear Fuel; Order Modifying License (Effective Immediately) I. The licensees identified in...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-12-20
... NUCLEAR REGULATORY COMMISSION [Docket Nos. (Redacted), License Nos.: (Redacted), EA (Redacted); NRC- 2010-0351] In the Matter of All Power Reactor Licensees and Research Reactor Licensees Who Transport Spent Nuclear Fuel; Order Modifying License (Effective Immediately) I The licensees identified in...
Gomez, Ana; Cardoso, Christiane; Genta, Fernando A; Terra, Walter R; Ferreira, Clélia
2013-08-01
The soluble midgut trehalase from Tenebrio molitor (TmTre1) was purified after several chromatographic steps, resulting in an enzyme with 58 kDa and pH optimum 5.3 (ionizing active groups in the free enzyme: pK(e1) = 3.8 ± 0.2 pK(e2) = 7.4 ± 0.2). The purified enzyme corresponds to the deduced amino acid sequence of a cloned cDNA (TmTre1-cDNA), because a single cDNA coding a soluble trehalase was found in the T. molitor midgut transcriptome. Furthermore, the mass of the protein predicted to be coded by TmTre1-cDNA agrees with that of the purified enzyme. TmTre1 has the essential catalytic groups Asp 315 and Glu 513 and the essential Arg residues R164, R217, R282. Carbodiimide inactivation of the purified enzyme at different pH values reveals an essential carboxyl group with pKa = 3.5 ± 0.3. Phenylglyoxal modified a single Arg residue with pKa = 7.5 ± 0.2, as observed in the soluble trehalase from Spodoptera frugiperda (SfTre1). Diethylpyrocarbonate modified a His residue that resulted in a less active enzyme with pK(e1) changed to 4.8 ± 0.2. In TmTre1 the modified His residue (putatively His 336) is more exposed than the His modified in SfTre1 (putatively His 210) and that affects the ionization of an Arg residue. The architecture of the active site of TmTre1 and SfTre1 is different, as shown by multiple inhibition analysis, the meaning of which demands further research. Trehalase sequences obtained from midgut transcriptomes (pyrosequencing and Illumina data) from 8 insects pertaining to 5 different orders were used in a cladogram, together with other representative sequences. The data suggest that the trehalase gene went duplication and divergence prior to the separation of the paraneopteran and holometabolan orders and that the soluble trehalase derived from the membrane-bound one by losing the C-terminal transmembrane loop. Copyright © 2013 Elsevier Ltd. All rights reserved.
Kroj, Thomas; Chanclud, Emilie; Michel-Romiti, Corinne; Grand, Xavier; Morel, Jean-Benoit
2016-04-01
Plant immune receptors of the class of nucleotide-binding and leucine-rich repeat domain (NLR) proteins can contain additional domains besides canonical NB-ARC (nucleotide-binding adaptor shared by APAF-1, R proteins, and CED-4 (NB-ARC)) and leucine-rich repeat (LRR) domains. Recent research suggests that these additional domains act as integrated decoys recognizing effectors from pathogens. Proteins homologous to integrated decoys are suspected to be effector targets and involved in disease or resistance. Here, we scrutinized 31 entire plant genomes to identify putative integrated decoy domains in NLR proteins using the Interpro search. The involvement of the Zinc Finger-BED type (ZBED) protein containing a putative decoy domain, called BED, in rice (Oryza sativa) resistance was investigated by evaluating susceptibility to the blast fungus Magnaporthe oryzae in rice over-expression and knock-out mutants. This analysis showed that all plants tested had integrated various atypical protein domains into their NLR proteins (on average 3.5% of all NLR proteins). We also demonstrated that modifying the expression of the ZBED gene modified disease susceptibility. This study suggests that integration of decoy domains in NLR immune receptors is widespread and frequent in plants. The integrated decoy model is therefore a powerful concept to identify new proteins involved in disease resistance. Further in-depth examination of additional domains in NLR proteins promises to unravel many new proteins of the plant immune system. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.
Candida albicans Utilizes a Modified β-Oxidation Pathway for the Degradation of Toxic Propionyl-CoA*
Otzen, Christian; Bardl, Bettina; Jacobsen, Ilse D.; Nett, Markus; Brock, Matthias
2014-01-01
Propionyl-CoA arises as a metabolic intermediate from the degradation of propionate, odd-chain fatty acids, and some amino acids. Thus, pathways for catabolism of this intermediate have evolved in all kingdoms of life, preventing the accumulation of toxic propionyl-CoA concentrations. Previous studies have shown that fungi generally use the methyl citrate cycle for propionyl-CoA degradation. Here, we show that this is not the case for the pathogenic fungus Candida albicans despite its ability to use propionate and valerate as carbon sources. Comparative proteome analyses suggested the presence of a modified β-oxidation pathway with the key intermediate 3-hydroxypropionate. Gene deletion analyses confirmed that the enoyl-CoA hydratase/dehydrogenase Fox2p, the putative 3-hydroxypropionyl-CoA hydrolase Ehd3p, the 3-hydroxypropionate dehydrogenase Hpd1p, and the putative malonate semialdehyde dehydrogenase Ald6p essentially contribute to propionyl-CoA degradation and its conversion to acetyl-CoA. The function of Hpd1p was further supported by the detection of accumulating 3-hydroxypropionate in the hpd1 mutant on propionyl-CoA-generating nutrients. Substrate specificity of Hpd1p was determined from recombinant purified enzyme, which revealed a preference for 3-hydroxypropionate, although serine and 3-hydroxyisobutyrate could also serve as substrates. Finally, virulence studies in a murine sepsis model revealed attenuated virulence of the hpd1 mutant, which indicates generation of propionyl-CoA from host-provided nutrients during infection. PMID:24497638
Acute Liver Injury Induces Nucleocytoplasmic Redistribution of Hepatic Methionine Metabolism Enzymes
Delgado, Miguel; Garrido, Francisco; Pérez-Miguelsanz, Juliana; Pacheco, María; Partearroyo, Teresa; Pérez-Sala, Dolores
2014-01-01
Abstract Aims: The discovery of methionine metabolism enzymes in the cell nucleus, together with their association with key nuclear processes, suggested a putative relationship between alterations in their subcellular distribution and disease. Results: Using the rat model of d-galactosamine intoxication, severe changes in hepatic steady-state mRNA levels were found; the largest decreases corresponded to enzymes exhibiting the highest expression in normal tissue. Cytoplasmic protein levels, activities, and metabolite concentrations suffered more moderate changes following a similar trend. Interestingly, galactosamine treatment induced hepatic nuclear accumulation of methionine adenosyltransferase (MAT) α1 and S-adenosylhomocysteine hydrolase tetramers, their active assemblies. In fact, galactosamine-treated livers showed enhanced nuclear MAT activity. Acetaminophen (APAP) intoxication mimicked most galactosamine effects on hepatic MATα1, including accumulation of nuclear tetramers. H35 cells that overexpress tagged-MATα1 reproduced the subcellular distribution observed in liver, and the changes induced by galactosamine and APAP that were also observed upon glutathione depletion by buthionine sulfoximine. The H35 nuclear accumulation of tagged-MATα1 induced by these agents correlated with decreased glutathione reduced form/glutathione oxidized form ratios and was prevented by N-acetylcysteine (NAC) and glutathione ethyl ester. However, the changes in epigenetic modifications associated with tagged-MATα1 nuclear accumulation were only prevented by NAC in galactosamine-treated cells. Innovation: Cytoplasmic and nuclear changes in proteins that regulate the methylation index follow opposite trends in acute liver injury, their nuclear accumulation showing potential as disease marker. Conclusion: Altogether these results demonstrate galactosamine- and APAP-induced nuclear accumulation of methionine metabolism enzymes as active oligomers and unveil the implication of redox-dependent mechanisms in the control of MATα1 subcellular distribution. Antioxid. Redox Signal. 20, 2541–2554. PMID:24124652
Process for cesium decontamination and immobilization
Komarneni, Sridhar; Roy, Rustum
1989-01-01
Cesium can be selectively recovered from a nuclear waste solution containing cesium together with other metal ions by contact with a modified phlogopite which is a hydrated, sodium phlogopite mica. Once the cesium has entered the modified phlogopite it is fixed and can be safely stored for long periods of time.
Candidate genetic modifiers for breast and ovarian cancer risk in BRCA1 and BRCA2 mutation carriers
Peterlongo, Paolo; Chang-Claude, Jenny; Moysich, Kirsten B.; Rudolph, Anja; Schmutzler, Rita K.; Simard, Jacques; Soucy, Penny; Eeles, Rosalind A.; Easton, Douglas F.; Hamann, Ute; Wilkening, Stefan; Chen, Bowang; Rookus, Matti A.; Schmidt, Marjanka K; van der Baan, Frederieke H.; Spurdle, Amanda B.; Walker, Logan C.; Lose, Felicity; Maia, Ana-Teresa; Montagna, Marco; Matricardi, Laura; Lubinski, Jan; Jakubowska, Anna; Gómez Garcia, Encarna B.; Olopade, Olufunmilayo I.; Nussbaum, Robert L.; Nathanson, Katherine L.; Domchek, Susan M.; Rebbeck, Timothy R.; Arun, Banu K.; Karlan, Beth Y.; Orsulic, Sandra; Lester, Jenny; Chung, Wendy K.; Miron, Alex; Southey, Melissa C.; Goldgar, David E.; Buys, Saundra S.; Janavicius, Ramunas; Dorfling, Cecilia M.; van Rensburg, Elizabeth J.; Ding, Yuan Chun; Neuhausen, Susan L.; Hansen, Thomas V. O.; Gerdes, Anne-Marie; Ejlertsen, Bent; Jønson, Lars; Osorio, Ana; Martínez-Bouzas, Cristina; Benitez, Javier; Conway, Edye E.; Blazer, Kathleen R.; Weitzel, Jeffrey N.; Manoukian, Siranoush; Peissel, Bernard; Zaffaroni, Daniela; Scuvera, Giulietta; Barile, Monica; Ficarazzi, Filomena; Mariette, Frederique; Fortuzzi, Stefano; Viel, Alessandra; Giannini, Giuseppe; Papi, Laura; Martayan, Aline; Tibiletti, Maria Grazia; Radice, Paolo; Vratimos, Athanassios; Fostira, Florentia; Garber, Judy E.; Donaldson, Alan; Brewer, Carole; Foo, Claire; Evans, D. Gareth R.; Frost, Debra; Eccles, Diana; Brady, Angela; Cook, Jackie; Tischkowitz, Marc; Adlard, Julian; Barwell, Julian; Walker, Lisa; Izatt, Louise; Side, Lucy E.; Kennedy, M. John; Rogers, Mark T.; Porteous, Mary E.; Morrison, Patrick J.; Platte, Radka; Davidson, Rosemarie; Hodgson, Shirley V.; Ellis, Steve; Cole, Trevor; Godwin, Andrew K.; Claes, Kathleen; Van Maerken, Tom; Meindl, Alfons; Gehrig, Andrea; Sutter, Christian; Engel, Christoph; Niederacher, Dieter; Steinemann, Doris; Plendl, Hansjoerg; Kast, Karin; Rhiem, Kerstin; Ditsch, Nina; Arnold, Norbert; Varon-Mateeva, Raymonda; Wappenschmidt, Barbara; Wang-Gohrke, Shan; Bressac-de Paillerets, Brigitte; Buecher, Bruno; Delnatte, Capucine; Houdayer, Claude; Stoppa-Lyonnet, Dominique; Damiola, Francesca; Coupier, Isabelle; Barjhoux, Laure; Venat-Bouvet, Laurence; Golmard, Lisa; Boutry-Kryza, Nadia; Sinilnikova, Olga M.; Caron, Olivier; Pujol, Pascal; Mazoyer, Sylvie; Belotti, Muriel; Piedmonte, Marion; Friedlander, Michael L.; Rodriguez, Gustavo C.; Copeland, Larry J; de la Hoya, Miguel; Segura, Pedro Perez; Nevanlinna, Heli; Aittomäki, Kristiina; van Os, Theo A.M.; Meijers-Heijboer, Hanne E.J.; van der Hout, Annemarie H.; Vreeswijk, Maaike P.G.; Hoogerbrugge, Nicoline; Ausems, Margreet G.E.M.; van Doorn, Helena C.; Collée, J. Margriet; Olah, Edith; Diez, Orland; Blanco, Ignacio; Lazaro, Conxi; Brunet, Joan; Feliubadalo, Lidia; Cybulski, Cezary; Gronwald, Jacek; Durda, Katarzyna; Jaworska-Bieniek, Katarzyna; Sukiennicki, Grzegorz; Arason, Adalgeir; Chiquette, Jocelyne; Teixeira, Manuel R.; Olswold, Curtis; Couch, Fergus J.; Lindor, Noralane M.; Wang, Xianshu; Szabo, Csilla I.; Offit, Kenneth; Corines, Marina; Jacobs, Lauren; Robson, Mark E.; Zhang, Liying; Joseph, Vijai; Berger, Andreas; Singer, Christian F.; Rappaport, Christine; Kaulich, Daphne Geschwantler; Pfeiler, Georg; Tea, Muy-Kheng M.; Phelan, Catherine M.; Greene, Mark H.; Mai, Phuong L.; Rennert, Gad; Mulligan, Anna Marie; Glendon, Gord; Tchatchou, Sandrine; Andrulis, Irene L.; Toland, Amanda Ewart; Bojesen, Anders; Pedersen, Inge Sokilde; Thomassen, Mads; Jensen, Uffe Birk; Laitman, Yael; Rantala, Johanna; von Wachenfeldt, Anna; Ehrencrona, Hans; Askmalm, Marie Stenmark; Borg, Åke; Kuchenbaecker, Karoline B.; McGuffog, Lesley; Barrowdale, Daniel; Healey, Sue; Lee, Andrew; Pharoah, Paul D.P.; Chenevix-Trench, Georgia; Antoniou, Antonis C.; Friedman, Eitan
2014-01-01
Background BRCA1 and BRCA2 mutation carriers are at substantially increased risk for developing breast and ovarian cancer. The incomplete penetrance coupled with the variable age at diagnosis in carriers of the same mutation suggests the existence of genetic and non-genetic modifying factors. In this study we evaluated the putative role of variants in many candidate modifier genes. Methods Genotyping data from 15,252 BRCA1 and 8,211 BRCA2 mutation carriers, for known variants (n=3,248) located within or around 445 candidate genes, were available through the iCOGS custom-designed array. Breast and ovarian cancer association analysis was performed within a retrospective cohort approach. Results The observed p-values of association ranged between 0.005-1.000. None of the variants was significantly associated with breast or ovarian cancer risk in either BRCA1 or BRCA2 mutation carriers, after multiple testing adjustments. Conclusion There is little evidence that any of the evaluated candidate variants act as modifiers of breast and/or ovarian cancer risk in BRCA1 or BRCA2 mutation carriers. Impact Genome-wide association studies have been more successful at identifying genetic modifiers of BRCA1/2 penetrance than candidate gene studies. PMID:25336561
Candidate genetic modifiers for breast and ovarian cancer risk in BRCA1 and BRCA2 mutation carriers.
Peterlongo, Paolo; Chang-Claude, Jenny; Moysich, Kirsten B; Rudolph, Anja; Schmutzler, Rita K; Simard, Jacques; Soucy, Penny; Eeles, Rosalind A; Easton, Douglas F; Hamann, Ute; Wilkening, Stefan; Chen, Bowang; Rookus, Matti A; Schmidt, Marjanka K; van der Baan, Frederieke H; Spurdle, Amanda B; Walker, Logan C; Lose, Felicity; Maia, Ana-Teresa; Montagna, Marco; Matricardi, Laura; Lubinski, Jan; Jakubowska, Anna; Gómez Garcia, Encarna B; Olopade, Olufunmilayo I; Nussbaum, Robert L; Nathanson, Katherine L; Domchek, Susan M; Rebbeck, Timothy R; Arun, Banu K; Karlan, Beth Y; Orsulic, Sandra; Lester, Jenny; Chung, Wendy K; Miron, Alex; Southey, Melissa C; Goldgar, David E; Buys, Saundra S; Janavicius, Ramunas; Dorfling, Cecilia M; van Rensburg, Elizabeth J; Ding, Yuan Chun; Neuhausen, Susan L; Hansen, Thomas V O; Gerdes, Anne-Marie; Ejlertsen, Bent; Jønson, Lars; Osorio, Ana; Martínez-Bouzas, Cristina; Benitez, Javier; Conway, Edye E; Blazer, Kathleen R; Weitzel, Jeffrey N; Manoukian, Siranoush; Peissel, Bernard; Zaffaroni, Daniela; Scuvera, Giulietta; Barile, Monica; Ficarazzi, Filomena; Mariette, Frederique; Fortuzzi, Stefano; Viel, Alessandra; Giannini, Giuseppe; Papi, Laura; Martayan, Aline; Tibiletti, Maria Grazia; Radice, Paolo; Vratimos, Athanassios; Fostira, Florentia; Garber, Judy E; Donaldson, Alan; Brewer, Carole; Foo, Claire; Evans, D Gareth R; Frost, Debra; Eccles, Diana; Brady, Angela; Cook, Jackie; Tischkowitz, Marc; Adlard, Julian; Barwell, Julian; Walker, Lisa; Izatt, Louise; Side, Lucy E; Kennedy, M John; Rogers, Mark T; Porteous, Mary E; Morrison, Patrick J; Platte, Radka; Davidson, Rosemarie; Hodgson, Shirley V; Ellis, Steve; Cole, Trevor; Godwin, Andrew K; Claes, Kathleen; Van Maerken, Tom; Meindl, Alfons; Gehrig, Andrea; Sutter, Christian; Engel, Christoph; Niederacher, Dieter; Steinemann, Doris; Plendl, Hansjoerg; Kast, Karin; Rhiem, Kerstin; Ditsch, Nina; Arnold, Norbert; Varon-Mateeva, Raymonda; Wappenschmidt, Barbara; Wang-Gohrke, Shan; Bressac-de Paillerets, Brigitte; Buecher, Bruno; Delnatte, Capucine; Houdayer, Claude; Stoppa-Lyonnet, Dominique; Damiola, Francesca; Coupier, Isabelle; Barjhoux, Laure; Venat-Bouvet, Laurence; Golmard, Lisa; Boutry-Kryza, Nadia; Sinilnikova, Olga M; Caron, Olivier; Pujol, Pascal; Mazoyer, Sylvie; Belotti, Muriel; Piedmonte, Marion; Friedlander, Michael L; Rodriguez, Gustavo C; Copeland, Larry J; de la Hoya, Miguel; Segura, Pedro Perez; Nevanlinna, Heli; Aittomäki, Kristiina; van Os, Theo A M; Meijers-Heijboer, Hanne E J; van der Hout, Annemarie H; Vreeswijk, Maaike P G; Hoogerbrugge, Nicoline; Ausems, Margreet G E M; van Doorn, Helena C; Collée, J Margriet; Olah, Edith; Diez, Orland; Blanco, Ignacio; Lazaro, Conxi; Brunet, Joan; Feliubadalo, Lidia; Cybulski, Cezary; Gronwald, Jacek; Durda, Katarzyna; Jaworska-Bieniek, Katarzyna; Sukiennicki, Grzegorz; Arason, Adalgeir; Chiquette, Jocelyne; Teixeira, Manuel R; Olswold, Curtis; Couch, Fergus J; Lindor, Noralane M; Wang, Xianshu; Szabo, Csilla I; Offit, Kenneth; Corines, Marina; Jacobs, Lauren; Robson, Mark E; Zhang, Liying; Joseph, Vijai; Berger, Andreas; Singer, Christian F; Rappaport, Christine; Kaulich, Daphne Geschwantler; Pfeiler, Georg; Tea, Muy-Kheng M; Phelan, Catherine M; Greene, Mark H; Mai, Phuong L; Rennert, Gad; Mulligan, Anna Marie; Glendon, Gord; Tchatchou, Sandrine; Andrulis, Irene L; Toland, Amanda Ewart; Bojesen, Anders; Pedersen, Inge Sokilde; Thomassen, Mads; Jensen, Uffe Birk; Laitman, Yael; Rantala, Johanna; von Wachenfeldt, Anna; Ehrencrona, Hans; Askmalm, Marie Stenmark; Borg, Åke; Kuchenbaecker, Karoline B; McGuffog, Lesley; Barrowdale, Daniel; Healey, Sue; Lee, Andrew; Pharoah, Paul D P; Chenevix-Trench, Georgia; Antoniou, Antonis C; Friedman, Eitan
2015-01-01
BRCA1 and BRCA2 mutation carriers are at substantially increased risk for developing breast and ovarian cancer. The incomplete penetrance coupled with the variable age at diagnosis in carriers of the same mutation suggests the existence of genetic and nongenetic modifying factors. In this study, we evaluated the putative role of variants in many candidate modifier genes. Genotyping data from 15,252 BRCA1 and 8,211 BRCA2 mutation carriers, for known variants (n = 3,248) located within or around 445 candidate genes, were available through the iCOGS custom-designed array. Breast and ovarian cancer association analysis was performed within a retrospective cohort approach. The observed P values of association ranged between 0.005 and 1.000. None of the variants was significantly associated with breast or ovarian cancer risk in either BRCA1 or BRCA2 mutation carriers, after multiple testing adjustments. There is little evidence that any of the evaluated candidate variants act as modifiers of breast and/or ovarian cancer risk in BRCA1 or BRCA2 mutation carriers. Genome-wide association studies have been more successful at identifying genetic modifiers of BRCA1/2 penetrance than candidate gene studies. ©2014 American Association for Cancer Research.
Hashimoto, Syougo; Okizaki, Kouhei; Kanesaki, Yu; Yoshikawa, Hirofumi; Yamakawa, Takeo
2015-01-01
The nodulation of Bradyrhizobium japonicum Is-34 is restricted by Rj4 genotype soybeans (Glycine max). To identify the genes responsible for this incompatibility, Tn5 mutants of B. japonicum Is-34 that were able to overcome this nodulation restriction were obtained. Analysis of the Tn5 mutants revealed that Tn5 was inserted into a region containing the MA20_12780 gene. In addition, direct disruption of this gene using marker exchange overcame the nodulation restriction by Rj4 genotype soybeans. The MA20_12780 gene has a tts box motif in its upstream region, indicating a possibility that this gene encodes a type III secretion system (T3SS) effector protein. Bioinformatic characterization revealed that the MA20_12780 protein contains the small ubiquitin-like modifier (SUMO) protease domain of the C48 peptidase (ubiquitin-like protease 1 [Ulp1]) family. The results of the present study indicate that a putative T3SS effector encoded by the MA20_12780 gene causes the incompatibility with Rj4 genotype soybeans, and they suggest the possibility that the nodulation restriction of B. japonicum Is-34 may be due to Rj4 genotype soybeans recognizing the putative T3SS effector (MA20_12780 protein) as a virulence factor. PMID:26092458
Tsurumaru, Hirohito; Hashimoto, Syougo; Okizaki, Kouhei; Kanesaki, Yu; Yoshikawa, Hirofumi; Yamakawa, Takeo
2015-09-01
The nodulation of Bradyrhizobium japonicum Is-34 is restricted by Rj4 genotype soybeans (Glycine max). To identify the genes responsible for this incompatibility, Tn5 mutants of B. japonicum Is-34 that were able to overcome this nodulation restriction were obtained. Analysis of the Tn5 mutants revealed that Tn5 was inserted into a region containing the MA20_12780 gene. In addition, direct disruption of this gene using marker exchange overcame the nodulation restriction by Rj4 genotype soybeans. The MA20_12780 gene has a tts box motif in its upstream region, indicating a possibility that this gene encodes a type III secretion system (T3SS) effector protein. Bioinformatic characterization revealed that the MA20_12780 protein contains the small ubiquitin-like modifier (SUMO) protease domain of the C48 peptidase (ubiquitin-like protease 1 [Ulp1]) family. The results of the present study indicate that a putative T3SS effector encoded by the MA20_12780 gene causes the incompatibility with Rj4 genotype soybeans, and they suggest the possibility that the nodulation restriction of B. japonicum Is-34 may be due to Rj4 genotype soybeans recognizing the putative T3SS effector (MA20_12780 protein) as a virulence factor. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
Dauncey, M J; Rudd, B T; White, D A; Shakespear, R A
1993-09-01
The regulation of plasma insulin-like growth factor binding proteins (IGFBPs) by energy status has been assessed in 2-month-old pigs. Energy balance was modified by altering thermoregulatory demand and energy intake, with litter-mates being kept for several weeks at either 35 or 10 degrees C on a high (H) or low (L) level of food intake (where H = 2L); plasma samples were taken 20-24 h after the last meal. The two major forms of circulating IGFBP, as estimated by Western blot analysis, were identified putatively as IGFBP-2 and IGFBP-3 (relative molecular weights of 34 and 40-45 kDa respectively). There were significant differences in IGFBP profiles between the four treatment groups of 35H, 35L, 10H and 10L: the 40-45 kDa IGFBP (putative IGFBP-3) was elevated both in the warm and on a high food intake (P < 0.001), and there was a marked reciprocal relation between the 40-45 and 34 kDa IGFBPs. The relative concentration of the 34 kDa IGFBP (putative IGFBP-2) was greatest in the 10L and least in the 35H group. It is concluded that long-term alterations in energy balance, induced by changes in either intake or thermoregulatory demand, can significantly affect the plasma profile of IGFBPs during the first two months of life.
Bruque, Carlos D; Delea, Marisol; Fernández, Cecilia S; Orza, Juan V; Taboas, Melisa; Buzzalino, Noemí; Espeche, Lucía D; Solari, Andrea; Luccerini, Verónica; Alba, Liliana; Nadra, Alejandro D; Dain, Liliana
2016-12-14
Congenital adrenal hyperplasia due to 21-hydroxylase deficiency accounts for 90-95% of CAH cases. In this work we performed an extensive survey of mutations and SNPs modifying the coding sequence of the CYP21A2 gene. Using bioinformatic tools and two plausible CYP21A2 structures as templates, we initially classified all known mutants (n = 343) according to their putative functional impacts, which were either reported in the literature or inferred from structural models. We then performed a detailed analysis on the subset of mutations believed to exclusively impact protein stability. For those mutants, the predicted stability was calculated and correlated with the variant's expected activity. A high concordance was obtained when comparing our predictions with available in vitro residual activities and/or the patient's phenotype. The predicted stability and derived activity of all reported mutations and SNPs lacking functional assays (n = 108) were assessed. As expected, most of the SNPs (52/76) showed no biological implications. Moreover, this approach was applied to evaluate the putative synergy that could emerge when two mutations occurred in cis. In addition, we propose a putative pathogenic effect of five novel mutations, p.L107Q, p.L122R, p.R132H, p.P335L and p.H466fs, found in 21-hydroxylase deficient patients of our cohort.
Bruque, Carlos D.; Delea, Marisol; Fernández, Cecilia S.; Orza, Juan V.; Taboas, Melisa; Buzzalino, Noemí; Espeche, Lucía D.; Solari, Andrea; Luccerini, Verónica; Alba, Liliana; Nadra, Alejandro D.; Dain, Liliana
2016-01-01
Congenital adrenal hyperplasia due to 21-hydroxylase deficiency accounts for 90–95% of CAH cases. In this work we performed an extensive survey of mutations and SNPs modifying the coding sequence of the CYP21A2 gene. Using bioinformatic tools and two plausible CYP21A2 structures as templates, we initially classified all known mutants (n = 343) according to their putative functional impacts, which were either reported in the literature or inferred from structural models. We then performed a detailed analysis on the subset of mutations believed to exclusively impact protein stability. For those mutants, the predicted stability was calculated and correlated with the variant’s expected activity. A high concordance was obtained when comparing our predictions with available in vitro residual activities and/or the patient’s phenotype. The predicted stability and derived activity of all reported mutations and SNPs lacking functional assays (n = 108) were assessed. As expected, most of the SNPs (52/76) showed no biological implications. Moreover, this approach was applied to evaluate the putative synergy that could emerge when two mutations occurred in cis. In addition, we propose a putative pathogenic effect of five novel mutations, p.L107Q, p.L122R, p.R132H, p.P335L and p.H466fs, found in 21-hydroxylase deficient patients of our cohort. PMID:27966633
Vamberger, Melita; Hofmeyr, Margaretha D; Ihlow, Flora; Fritz, Uwe
2018-01-01
Based on rangewide sampling and three mitochondrial and two nuclear markers (together up to 1,850 bp and 1,840 bp, respectively), we examine the phylogeography of two helmeted terrapin species ( Pelomedusa galeata and P. subrufa sensu stricto) and infer shifts of climatically suitable spaces since the Last Glacial Maximum using a modeling approach. Whilst P. galeata displays significant phylogeographic structuring across its range and consists of two deeply divergent lineages that could represent distinct species, P. subrufa shows no obvious phylogeographic differentiation. This seems to be related to historically stable or fluctuating ranges. One of the lineages within P. galeata appears to be confined to the westernmost, winter-rainfall region of South Africa and deserves special conservational attention due to the scarcity of surface water. The other lineage is distributed further east and is differentiated in three weakly supported subclades with parapatric distribution; one occurring inland, and two along the south and east coasts, respectively. As far as is known, P. subrufa occurs in South Africa only in the northeast of the country (Limpopo, Mpumalanga) and we report the species for the first time from the Lapalala Wilderness Area in the Waterberg region (Limpopo), approximately 350 km further west than previously recorded. We confirmed the occurrence of P. galeata only 80 km south of Lapalala. Thus, a sympatric occurrence of P. galeata and P. subrufa is possible. Another putative contact zone, for the two lineages within P. galeata , must be located in the Western Cape region, and further contact zones are likely for the eastern subclades within P. galeata . The nuclear loci provided no evidence for gene flow across taxa or genetic clusters within taxa. Future investigations should use denser sampling from putative contact zones and more nuclear markers to re-examine this situation. Despite few phylogeographic studies published for southern African biota, it seems likely that differentiation follows general rules, and that climate and physiographic barriers (e.g., the Great Escarpment) have shaped phylogeographic patterns.
Nine microsatellite loci developed from the octocoral, Paragorgia arborea
Coykendall, D. Katharine; Morrison, Cheryl L.
2015-01-01
Paragorgia arborea, or bubblegum coral, occurs in continental slope habitats worldwide, which are increasingly threatened by human activities such as energy development and fisheries practices. From 101 putative loci screened, nine microsatellite markers were developed from samples taken from Baltimore canyon in the western North Atlantic Ocean. The number of alleles ranged from two to thirteen per locus and each displayed equilibrium. These nuclear resources will help further research on population connectivity in threatened coral species where mitochondrial markers are known to lack fine-scale genetic diversity.
The Effects of Modeled Microgravity on Nucleocytoplasmic Localization of Human Apurinic/Apyrimidinic
NASA Technical Reports Server (NTRS)
Gonda, Steve; Jackson, E.B.
2004-01-01
Exposure to space radiation and microgravity occurs to humans during space flight. In order to have accurate risk estimations, answering questions to whether increased DNA damage seen during space flight in modified by microgravity are important. Several studies have examined whether intercellular repair of radiation-induced DNA lesions are modified by microgravity. Results from these studies show no modification of the repair processes due to microgravity. However, it is known that in studies not involving radiation that microgravity interferes with normal development. Interestingly, there is no data that attempts to analyze the possible effects of microgravity on the trafficking of DNA repair proteins. In this study, we analyze the effects of modeled microgravity on nucleocytoplasmic shuttling of the human DNA repair enzyme apurinic/apyrimidinic endonuclease 1 (APE1/Ref1) which is involved in base excision repair. We examined nuclear translocation of APE1 using enhanced green fluorescent protein (EGFP) fused to APE1 as a reporter. While APE1 under normal gravity showed normal nuclear localization, APE1 nuclear localization under modeled microgravity was decreased. These results suggest that nucleocytoplasmic translocation of APE1 is modified under modeled microgravity.
Requirements to the procedure and stages of innovative fuel development
NASA Astrophysics Data System (ADS)
Troyanov, V.; Zabudko, L.; Grachyov, A.; Zhdanova, O.
2016-04-01
According to the accepted current understanding under the nuclear fuel we will consider the assembled active zone unit (Fuel assembly) with its structural elements, fuel rods, pellet column, structural materials of fuel rods and fuel assemblies. The licensing process includes justification of safe application of the proposed modifications, including design-basis and experimental justification of the modified items under normal operating conditions and in violation of normal conditions, including accidents as well. Besides the justification of modified units itself, it is required to show the influence of modifications on the performance and safety of the other Reactor Unit’ and Nuclear Plant’ elements (e.g. burst can detection system, transportation and processing operations during fuel handling), as well as to justify the new standards of fuel storage etc. Finally, the modified fuel should comply with the applicable regulations, which often becomes a very difficult task, if only because those regulations, such as the NP-082-07, are not covered modification issues. Making amendments into regulations can be considered as the only solution, but the process is complicated and requires deep grounds for amendments. Some aspects of licensing new nuclear fuel are considered the example of mixed nitride uranium -plutonium fuel application for the BREST reactor unit.
A putative homologue of CDC20/CDH1 in the malaria parasite is essential for male gamete development.
Guttery, David S; Ferguson, David J P; Poulin, Benoit; Xu, Zhengyao; Straschil, Ursula; Klop, Onny; Solyakov, Lev; Sandrini, Sara M; Brady, Declan; Nieduszynski, Conrad A; Janse, Chris J; Holder, Anthony A; Tobin, Andrew B; Tewari, Rita
2012-02-01
Cell-cycle progression is governed by a series of essential regulatory proteins. Two major regulators are cell-division cycle protein 20 (CDC20) and its homologue, CDC20 homologue 1 (CDH1), which activate the anaphase-promoting complex/cyclosome (APC/C) in mitosis, and facilitate degradation of mitotic APC/C substrates. The malaria parasite, Plasmodium, is a haploid organism which, during its life-cycle undergoes two stages of mitosis; one associated with asexual multiplication and the other with male gametogenesis. Cell-cycle regulation and DNA replication in Plasmodium was recently shown to be dependent on the activity of a number of protein kinases. However, the function of cell division cycle proteins that are also involved in this process, such as CDC20 and CDH1 is totally unknown. Here we examine the role of a putative CDC20/CDH1 in the rodent malaria Plasmodium berghei (Pb) using reverse genetics. Phylogenetic analysis identified a single putative Plasmodium CDC20/CDH1 homologue (termed CDC20 for simplicity) suggesting that Plasmodium APC/C has only one regulator. In our genetic approach to delete the endogenous cdc20 gene of P. berghei, we demonstrate that PbCDC20 plays a vital role in male gametogenesis, but is not essential for mitosis in the asexual blood stage. Furthermore, qRT-PCR analysis in parasite lines with deletions of two kinase genes involved in male sexual development (map2 and cdpk4), showed a significant increase in cdc20 transcription in activated gametocytes. DNA replication and ultra structural analyses of cdc20 and map2 mutants showed similar blockage of nuclear division at the nuclear spindle/kinetochore stage. CDC20 was phosphorylated in asexual and sexual stages, but the level of modification was higher in activated gametocytes and ookinetes. Changes in global protein phosphorylation patterns in the Δcdc20 mutant parasites were largely different from those observed in the Δmap2 mutant. This suggests that CDC20 and MAP2 are both likely to play independent but vital roles in male gametogenesis.
A Putative Homologue of CDC20/CDH1 in the Malaria Parasite Is Essential for Male Gamete Development
Guttery, David S.; Ferguson, David J. P.; Poulin, Benoit; Xu, Zhengyao; Straschil, Ursula; Klop, Onny; Solyakov, Lev; Sandrini, Sara M.; Brady, Declan; Nieduszynski, Conrad A.; Janse, Chris J.; Holder, Anthony A.; Tobin, Andrew B.; Tewari, Rita
2012-01-01
Cell-cycle progression is governed by a series of essential regulatory proteins. Two major regulators are cell-division cycle protein 20 (CDC20) and its homologue, CDC20 homologue 1 (CDH1), which activate the anaphase-promoting complex/cyclosome (APC/C) in mitosis, and facilitate degradation of mitotic APC/C substrates. The malaria parasite, Plasmodium, is a haploid organism which, during its life-cycle undergoes two stages of mitosis; one associated with asexual multiplication and the other with male gametogenesis. Cell-cycle regulation and DNA replication in Plasmodium was recently shown to be dependent on the activity of a number of protein kinases. However, the function of cell division cycle proteins that are also involved in this process, such as CDC20 and CDH1 is totally unknown. Here we examine the role of a putative CDC20/CDH1 in the rodent malaria Plasmodium berghei (Pb) using reverse genetics. Phylogenetic analysis identified a single putative Plasmodium CDC20/CDH1 homologue (termed CDC20 for simplicity) suggesting that Plasmodium APC/C has only one regulator. In our genetic approach to delete the endogenous cdc20 gene of P. berghei, we demonstrate that PbCDC20 plays a vital role in male gametogenesis, but is not essential for mitosis in the asexual blood stage. Furthermore, qRT-PCR analysis in parasite lines with deletions of two kinase genes involved in male sexual development (map2 and cdpk4), showed a significant increase in cdc20 transcription in activated gametocytes. DNA replication and ultra structural analyses of cdc20 and map2 mutants showed similar blockage of nuclear division at the nuclear spindle/kinetochore stage. CDC20 was phosphorylated in asexual and sexual stages, but the level of modification was higher in activated gametocytes and ookinetes. Changes in global protein phosphorylation patterns in the Δcdc20 mutant parasites were largely different from those observed in the Δmap2 mutant. This suggests that CDC20 and MAP2 are both likely to play independent but vital roles in male gametogenesis. PMID:22383885
Dechat, Thomas; Adam, Stephen A.; Taimen, Pekka; Shimi, Takeshi; Goldman, Robert D.
2010-01-01
The nuclear lamins are type V intermediate filament proteins that are critically important for the structural properties of the nucleus. In addition, they are involved in the regulation of numerous nuclear processes, including DNA replication, transcription and chromatin organization. The developmentally regulated expression of lamins suggests that they are involved in cellular differentiation. Their assembly dynamic properties throughout the cell cycle, particularly in mitosis, are influenced by posttranslational modifications. Lamins may regulate nuclear functions by direct interactions with chromatin and determining the spatial organization of chromosomes within the nuclear space. They may also regulate chromatin functions by interacting with factors that epigenetically modify the chromatin or directly regulate replication or transcription. PMID:20826548
Sulkowski, Michael L.; Geller, Daniel A.; Lewin, Adam B.; Murphy, Tanya K.; Mittelman, Andrew; Brown, Ashley; Storch, Eric A.
2014-01-01
Variants of exposure therapy are effective for treating obsessive-compulsive and related disorders (OCRDs). However, significant numbers of patients do not respond adequately to exposure therapy resulting in continued distress and functional impairment. Therefore, novel approaches to augmenting exposure therapy are needed to adequately treat non- and partial-responders. Emerging research suggests that interventions that augment learning and memory processes associated with exposure therapy (i.e., extinction training) may display promise in enhancing treatment response in OCRDs. As the most studied example, d-cycloserine (DCS) is a relatively safe cognitive enhancer that appears to accelerate treatment gains associated with exposure therapy. This article reviews research on the use of DCS and other putative cognitive modifiers as they relate to the treatment (or prospective treatment) of obsessive-compulsive disorder and other OCRDs. PMID:25383074
Piolot, Tristan; Tramier, Marc; Coppey, Maité; Nicolas, Jean-Claude; Marechal, Vincent
2001-01-01
Human herpesvirus 8 is associated with all forms of Kaposi's sarcoma, AIDS-associated body cavity-based lymphomas, and some forms of multicentric Castleman's disease. Herpesvirus 8, like other gammaherpesviruses, can establish a latent infection in which viral genomes are stably maintained as multiple episomes. The latent nuclear antigen (LANA or LNAI) may play an essential role in the stable maintenance of latent episomes, notably by interacting concomitantly with the viral genomes and the metaphase chromosomes, thus ensuring an efficient transmission of the neoduplicated episomes to the daughter cells. To identify the regions responsible for its nuclear and subnuclear localization in interphase and mitotic cells, LNAI and various truncated forms were fused to a variant of green fluorescent protein. This enabled their localization and chromosome binding activity to be studied by low-light-level fluorescence microscopy in living HeLa cells. The results demonstrate that nuclear localization of LNAI is due to a unique signal, which maps between amino acids 24 and 30. Interestingly, this nuclear localization signal closely resembles those identified in EBNA1 from Epstein-Barr virus and herpesvirus papio. A region encompassing amino acids 5 to 22 was further proved to mediate the specific interaction of LNA1 with chromatin during interphase and the chromosomes during mitosis. The presence of putative phosphorylation sites in the chromosome binding sites of LNA1 and EBNA1 suggests that their activity may be regulated by specific cellular kinases. PMID:11264383
Taming The Next Set of Strategic Weapons Threats
2006-06-01
Reactors Victor Gilinsky . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 6. Coping with Biological Threats after...Regime (MTCR) is not yet optimized to cope with these challenges. Finally, nuclear technologies have become much more difficult to control. New...resistance of the most popular type of power reactor concludes that the current international nuclear safeguards system needs to be modified to cope
Tao, Zhihua; Gao, Peng; Liu, Hung-Wen
2009-12-15
Poly(ADP-ribosyl)ation of various nuclear proteins catalyzed by a family of NAD(+)-dependent enzymes, poly(ADP-ribose) polymerases (PARPs), is an important posttranslational modification reaction. PARP activity has been demonstrated in all types of eukaryotic cells with the exception of yeast, in which the expression of human PARP-1 was shown to lead to retarded cell growth. We investigated the yeast growth inhibition caused by human PARP-1 expression in Saccharomyces cerevisiae. Flow cytometry analysis reveals that PARP-1-expressing yeast cells accumulate in the G(2)/M stage of the cell cycle. Confocal microscopy analysis shows that human PARP-1 is distributed throughout the nucleus of yeast cells but is enriched in the nucleolus. Utilizing yeast proteome microarray screening, we identified 33 putative PARP-1 substrates, six of which are known to be involved in ribosome biogenesis. The poly(ADP-ribosyl)ation of three of these yeast proteins, together with two human homologues, was confirmed by an in vitro PARP-1 assay. Finally, a polysome profile analysis using sucrose gradient ultracentrifugation demonstrated that the ribosome levels in yeast cells expressing PARP-1 are lower than those in control yeast cells. Overall, our data suggest that human PARP-1 may affect ribosome biogenesis by modifying certain nucleolar proteins in yeast. The artificial PARP-1 pathway in yeast may be used as a simple platform to identify substrates and verify function of this important enzyme.
Marin, Ethan P.; Derakhshan, Behrad; Lam, TuKiet T.; Davalos, Alberto; Sessa, William C.
2012-01-01
Rationale Protein S-palmitoylation is the post-translational attachment of a saturated 16-carbon palmitic acid to a cysteine side chain via a thioester bond. Palmitoylation can affect protein localization, trafficking, stability, and function. The extent and roles of palmitoylation in endothelial cell (EC) biology is not well understood, in part due to technological limits on palmitoylprotein detection. Objective To develop a method using acyl-biotinyl exchange (ABE) technology coupled with mass spectrometry to globally isolate and identify palmitoylproteins in EC. Methods and Results More than 150 putative palmitoyl proteins were identified in EC using ABE and mass spectrometry. Among the novel palmitoylproteins identified is superoxide dismutase 1 (SOD1), an intensively studied enzyme that protects all cells from oxidative damage. Mutation of cysteine 6 prevents palmitoylation, leads to reduction in SOD1 activity in vivo and in vitro, and inhibits nuclear localization, thereby supporting a functional role for SOD1 palmitoylation. Moreover, we used ABE to search for substrates of particular protein acyl transferases in EC. We found that palmitoylation of the cell adhesion protein PECAM1 is dependent on the protein acyl transferase ZDHHC21. We show that knockdown of ZDHHC21 leads to reduced levels of PECAM1 at the cell surface. Conclusions Our data demonstrate the utility of EC palmitoylproteomics to reveal new insights into the role of this important post-translational lipid modification in EC biology. PMID:22496122
Setoguchi, H; Watanabe, I
2000-06-01
Hybridization and introgression play important roles in plant evolution, and their occurrence on the oceanic islands provides good examples of plant speciation and diversification. Restriction fragment length polymorphisms (RFLPs) and trnL (UAA) 3'exon-trnF (GAA) intergenic spacer (IGS) sequences of chloroplast DNA (cpDNA), and the sequences of internal transcribed spacer (ITS) of nuclear ribosomal DNA were examined to investigate the occurrence of gene transfer in Ilex species on the Bonin Islands and the Ryukyu Islands in Japan. A gene phylogeny for the plastid genome is in agreement with the morphologically based taxonomy, whereas the nuclear genome phylogeny clusters putatively unrelated endemics both on the Bonin and the Ryukyu Islands. Intersectional hybridization and nuclear gene flow were independently observed in insular endemics of Ilex on both sets of islands without evidence of plastid introgression. Gene flow observed in these island systems can be explained by ecological features of insular endemics, i.e., limits of distribution range or sympatric distribution in a small land area.
Quantum indistinguishability in chemical reactions.
Fisher, Matthew P A; Radzihovsky, Leo
2018-05-15
Quantum indistinguishability plays a crucial role in many low-energy physical phenomena, from quantum fluids to molecular spectroscopy. It is, however, typically ignored in most high-temperature processes, particularly for ionic coordinates, implicitly assumed to be distinguishable, incoherent, and thus well approximated classically. We explore enzymatic chemical reactions involving small symmetric molecules and argue that in many situations a full quantum treatment of collective nuclear degrees of freedom is essential. Supported by several physical arguments, we conjecture a "quantum dynamical selection" (QDS) rule for small symmetric molecules that precludes chemical processes that involve direct transitions from orbitally nonsymmetric molecular states. As we propose and discuss, the implications of the QDS rule include ( i ) a differential chemical reactivity of para- and orthohydrogen, ( ii ) a mechanism for inducing intermolecular quantum entanglement of nuclear spins, ( iii ) a mass-independent isotope fractionation mechanism, ( iv ) an explanation of the enhanced chemical activity of "reactive oxygen species", ( v ) illuminating the importance of ortho-water molecules in modulating the quantum dynamics of liquid water, and ( vi ) providing the critical quantum-to-biochemical linkage in the nuclear spin model of the (putative) quantum brain, among others.
Ploidy levels among species in the 'Oxalis tuberosa alliance' as inferred by flow cytometry.
Emshwiller, Eve
2002-06-01
The 'Oxalis tuberosa alliance' is a group of Andean Oxalis species allied to the Andean tuber crop O. tuberosa Molina (Oxalidaceae), commonly known as 'oca'. As part of a larger project studying the origins of polyploidy and domestication of cultivated oca, flow cytometry was used to survey DNA ploidy levels among Bolivian and Peruvian accessions of alliance members. In addition, this study provided a first assessment of C-values in the alliance by estimating nuclear DNA contents of these accessions using chicken erythrocytes as internal standard. Ten Bolivian accessions of cultivated O. tuberosa were confirmed to be octoploid, with a mean nuclear DNA content of approx. 3.6 pg/2C. Two Peruvian wild Oxalis species, O. phaeotricha and O. picchensis, were inferred to be tetraploid (both with approx. 1.67 pg/2C), the latter being one of the putative progenitors of O. tuberosa identified by chloroplast-expressed glutamine synthetase data in prior work. The remaining accessions (from 78 populations provisionally identified as 35 species) were DNA diploid, with nuclear DNA contents varying from 0.79 to 1.34 pg/2C.
Process for cesium decontamination and immobilization
Komarneni, S.; Roy, R.
1988-04-25
Cesium can be selectively recovered from a nuclear waste solution containing cesium together with other metal ions by contact with a modified phlogopite which is a hydrated, sodium phlogopite mica. Once the cesium has entered the modified phlogopite it is fixed and can be safely stored for long periods of time. 6 figs., 2 tabs.
The Development of Models to Optimize Selection of Nuclear Fuels through Atomic-Level Simulation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Prof. Simon Phillpot; Prof. Susan B. Sinnott; Prof. Hans Seifert
2009-01-26
Demonstrated that FRAPCON can be modified to accept data generated from first principles studies, and that the result obtained from the modified FRAPCON make sense in terms of the inputs. Determined the temperature dependence of the thermal conductivity of single crystal UO2 from atomistic simulation.
Li, Zicong; He, Xiaoyan; Chen, Liwen; Shi, Junsong; Zhou, Rong; Xu, Weihua; Liu, Dewu; Wu, Zhenfang
2013-10-01
The somatic cell nuclear transfer (SCNT) technique has been widely applied to clone pigs or to produce genetically modified pigs. Currently, this technique relies mainly on using terminally differentiated fibroblasts as donor cells. To improve cloning efficiency, only partially differentiated multipotent mesenchymal stem cells (MSCs), thought to be more easily reprogrammed to a pluripotent state, have been used as nuclear donors in pig SCNT. Although in vitro-cultured embryos cloned from porcine MSCs (MSCs-embryos) were shown to have higher preimplantation developmental ability than cloned embryos reconstructed from fibroblasts (Fs-embryos), the difference in in vivo full-term developmental rate between porcine MSCs-embryos and Fs-embryos has not been investigated so far. In this study, we demonstrated that blastocyst total cell number and full-term survival abilities of MSCs-embryos were significantly higher than those of Fs-embryos cloned from the same donor pig. The enhanced developmental potential of MSCs-embryos may be associated with their nuclear donors' DNA methylation profile, because we found that the methylation level of imprinting genes and repeat sequences differed between MSCs and fibroblasts. In addition, we showed that use of transgenic porcine MSCs generated from transgene plasmid transfection as donor cells for SCNT can produce live transgenic cloned pigs. These results strongly suggest that porcine bone marrow MSCs are a desirable donor cell type for production of cloned pigs and genetically modified cloned pigs via SCNT.
Skvarc, David R; Berk, Michael; Byrne, Linda K; Dean, Olivia M; Dodd, Seetal; Lewis, Matthew; Marriott, Andrew; Moore, Eileen M; Morris, Gerwyn; Page, Richard S; Gray, Laura
2018-01-01
Post-Operative Cognitive Dysfunction (POCD) is a highly prevalent condition with significant clinical, social and financial impacts for patients and their communities. The underlying pathophysiology is becoming increasingly understood, with the role of neuroinflammation and oxidative stress secondary to surgery and anaesthesia strongly implicated. This review aims to describe the putative mechanisms by which surgery-induced inflammation produces cognitive sequelae, with a focus on identifying potential novel therapies based upon their ability to modify these pathways. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.
Venus: Mantle convection, hotspots, and tectonics
NASA Technical Reports Server (NTRS)
Phillips, R. J.
1989-01-01
The putative paradigm that planets of the same size and mass have the same tectonic style led to the adaptation of the mechanisms of terrestrial plate tectonics as the a priori model of the way Venus should behave. Data acquired over the last decade by Pioneer Venus, Venera, and ground-based radar have modified this view sharply and have illuminated the lack of detailed understanding of the plate tectonic mechanism. For reference, terrestrial mechanisms are briefly reviewed. Venusian lithospheric divergence, hotspot model, and horizontal deformation theories are proposed and examined.
Nuclear States with Abnormally Large Radii (size Isomers)
NASA Astrophysics Data System (ADS)
Ogloblin, A. A.; Demyanova, A. S.; Danilov, A. N.; Belyaeva, T. L.; Goncharov, S. A.
2015-06-01
Application of the methods of measuring the radii of the short-lived excited states (Modified diffraction model MDM, Inelastic nuclear rainbow scattering method INRS, Asymptotic normalization coefficients method ANC) to the analysis of some nuclear reactions provide evidence of existing in 9Be, 11B, 12C, 13C the excited states whose radii exceed those of the corresponding ground states by ~ 30%. Two types of structure of these "size isomers" were identified: neutron halo an α-clusters.
Baumsteiger, Jason; Kinziger, Andrew P; Aguilar, Andres
2012-12-01
The west coast of North America contains a number of biogeographic freshwater provinces which reflect an ever-changing aquatic landscape. Clues to understanding this complex structure are often encapsulated genetically in the ichthyofauna, though frequently as unresolved evolutionary relationships and putative cryptic species. Advances in molecular phylogenetics through species tree analyses now allow for improved exploration of these relationships. Using a comprehensive approach, we analyzed two mitochondrial and nine nuclear loci for a group of endemic freshwater fish (sculpin-Cottus) known for a wide ranging distribution and complex species structure in this region. Species delimitation techniques identified three novel cryptic lineages, all well supported by phylogenetic analyses. Comparative phylogenetic analyses consistently found five distinct clades reflecting a number of unique biogeographic provinces. Some internal node relationships varied by species tree reconstruction method, and were associated with either Bayesian or maximum likelihood statistical approaches or between mitochondrial, nuclear, and combined datasets. Limited cases of mitochondrial capture were also evident, suggestive of putative ancestral hybridization between species. Biogeographic diversification was associated with four major regions and revealed historical faunal exchanges across regions. Mapping of an important life-history character (amphidromy) revealed two separate instances of trait evolution, a transition that has occurred repeatedly in Cottus. This study demonstrates the power of current phylogenetic methods, the need for a comprehensive phylogenetic approach, and the potential for sculpin to serve as an indicator of biogeographic history for native ichthyofauna in the region. Copyright © 2012 Elsevier Inc. All rights reserved.
Kim, Bo-Mi; Rhee, Jae-Sung; Hwang, Un-Ki; Seo, Jung Soo; Shin, Kyung-Hoon; Lee, Jae-Seong
2015-02-01
The aryl hydrocarbon receptor (AhR) and aryl hydrocarbon nuclear translocator (ARNT) genes from the copepod Tigriopus japonicus (Tj) were cloned to examine their potential functions in the invertebrate putative AhR-CYP signaling pathway. The amino acid sequences encoded by the Tj-AhR and Tj-ARNT genes showed high similarity to homologs of Daphnia and Drosophila, ranging from 68% and 70% similarity for the AhR genes to 56% for the ARNT genes. To determine whether Tj-AhR and Tj-ARNT are modulated by environmental pollutants, transcriptional expression of Tj-AhR and Tj-ARNT was analyzed in response to exposure to five concentrations of polychlorinated biphenyl (PCB 126) (control, 10, 50, 100, 500 μg L(-1)), benzo[a]pyrene (B[a]P) (control, 5, 10, 50, 100 μg L(-1)), and tributyltin (TBT) (control, 1, 5, 10, 20 μg L(-1)) 24h after exposure. A time-course experiment (0, 3, 6, 12, 24h) was performed to analyze mRNA expression patterns after exposure to PCB, B[a]P, and TBT. T. japonicus exhibited dose-dependent and time-dependent upregulation of Tj-AhR and Tj-ARNT in response to pollutant exposure, and the degree of expression was dependent on the pollutant, suggesting that pollutants such as PCB, B[a]P, and TBT modulate expression of Tj-AhR and Tj-ARNT genes in the putative AhR-CYP signaling pathway. Copyright © 2014 Elsevier Ltd. All rights reserved.
Nuclear Receptors and AMPK: Can Exercise Mimetics Cure Diabetes?
Wall, Christopher E.; Yu, Ruth T.; Atkins, Anne R.; Downes, Michael; Evans, Ronald M.
2016-01-01
Endurance exercise can lead to systemic improvements in insulin sensitivity and metabolic homeostasis, and is an effective approach to combat metabolic diseases. Pharmacological compounds that recapitulate the beneficial effects of exercise, also known as “exercise mimetics,” have the potential to improve disease symptoms of metabolic syndrome. These drugs, which can increase energy expenditure, suppress hepatic gluconeogenesis, and induce insulin sensitization, have accordingly been highly scrutinized for their utility in treating metabolic diseases including diabetes. Nevertheless, the identity of an efficacious exercise mimetic still remains elusive. In this article, we will highlight several nuclear receptors and cofactors that are putative molecular targets for exercise mimetics, and review recent studies that provide advancements in our mechanistic understanding of how exercise mimetics exert their beneficial effects. We will also discuss evidence from clinical trials utilizing these compounds in human subjects to evaluate their efficacy in treating diabetes. PMID:27106806
DOE Office of Scientific and Technical Information (OSTI.GOV)
Abraitiene, Asta; US Department of Agriculture, Agricultural Research Service, Molecular Plant Pathology Laboratory, Room 214 Building 004 BARC-West, 10300 Baltimore Avenue, Beltsville, MD 20705; Zhao Yan
Transient expression of engineered reporter RNAs encoding an intron-containing green fluorescent protein (GFP) from a Potato virus X-based expression vector previously demonstrated the nuclear targeting capability of the 359 nucleotide Potato spindle tuber viroid (PSTVd) RNA genome. To further delimit the putative nuclear-targeting signal, PSTVd subgenomic fragments were embedded within the intron, and recombinant reporter RNAs were inoculated onto Nicotiana benthamiana plants. Appearance of green fluorescence in leaf tissue inoculated with PSTVd-fragment-containing constructs indicated shuttling of the RNA into the nucleus by fragments as short as 80 nucleotides in length. Plant-to-plant variation in the timing of intron removal and subsequentmore » GFP fluorescence was observed; however, earliest and most abundant GFP expression was obtained with constructs containing the conserved hairpin I palindrome structure and embedded upper central conserved region. Our results suggest that this conserved sequence and/or the stem-loop structure it forms is sufficient for import of PSTVd into the nucleus.« less
Impact of the 26mAl(p, γ) reaction to galactic 26Al yield
NASA Astrophysics Data System (ADS)
Kahl, D.; Shimizu, H.; Yamaguchi, H.; Abe, K.; Beliuskina, O.; Cha, S. M.; Chae, K. Y.; Chen, A. A.; Ge, Z.; Hayakawa, S.; Imai, N.; Iwasa, N.; Kim, A.; Kim, D. H.; Kim, M. J.; Kubono, S.; Kwag, M. S.; Liang, J.; Moon, J. Y.; Nishimura, S.; Oka, S.; Park, S. Y.; Psaltis, A.; Teranishi, T.; Ueno, Y.; Yang, L.
2018-04-01
Astrophysical observables that are directly linked to nuclear physics inputs provide critical and stringent constraints on nucleosynthetic models. As 26Al was the first specific radioactivity observed in the Galaxy, its origin has fascinated the nuclear astrophysics community for nearly forty years. Despite extensive research, the precise origins of 26Al remain elusive. At present, the sum of all putative stellar contributions generally overestimates the 26Al mass in the interstellar medium. Among the many reactions that influence the yield of 26Al, radiative proton capture on its isomer 26mAl is one of the least constrained reactions by experimental data. To this end, we developed a 26Al isomeric beam and performed proton elastic scattering to search for low-spin states in 27Si. The experimental method and the preliminary results of this on-going study will be presented.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hirano, Seishiro, E-mail: seishiro@nies.go.jp; Graduate School of Pharmaceutical Sciences, Chiba University; Tadano, Mihoko
2015-09-15
Promyelocytic leukemia (PML), which is a tumor suppressor protein that nevertheless plays an important role in the maintenance of leukemia initiating cells, is known to be biochemically modified by As{sup 3+}. We recently developed a simple method to evaluate the modification of PML by As{sup 3+} resulting in a change in solubility and the covalent binding of small ubiquitin-like modifier (SUMO). Here we semi-quantitatively investigated the SUMOylation of PML using HEK293 cells which were stably transfected with PML-VI (HEK-PML). Western blot analyses indicated that PML became insoluble in cold RadioImmunoPrecipitation Assay (RIPA) lysis buffer and was SUMOylated by both SUMO2/3more » and SUMO1 by As{sup 3+}. Surprisingly SUMO1 monomers were completely utilized for the SUMOylation of PML. Antimony (Sb{sup 3+}) but not bismuth (Bi{sup 3+}), Cu{sup 2+}, or Cd{sup 2+} biochemically modified PML similarly. SUMOylated PML decreased after removal of As{sup 3+} from the culture medium. However, unSUMOylated PML was still recovered in the RIPA-insoluble fraction, suggesting that SUMOylation is not requisite for changing the RIPA-soluble PML into the RIPA-insoluble form. Immunofluorescence staining of As{sup 3+}-exposed cells indicated that SUMO2/3 was co-localized with PML in the nuclear bodies. However, some PML protein was present in peri-nuclear regions without SUMO2/3. Functional Really Interesting New Gene (RING)-deleted mutant PML neither formed PML nuclear bodies nor was biochemically modified by As{sup 3+}. Conjugation with intracellular glutathione may explain the accessibility of As{sup 3+} and Sb{sup 3+} to PML in the nuclear region evading chelation and entrapping by cytoplasmic proteins such as metallothioneins. - Highlights: • As{sup 3+} is a carcinogen and also a therapeutic agent for leukemia. • PML becomes insoluble in RIPA and SUMOylated by As{sup 3+}. • Sb{sup 3+} modifies PML similar to As{sup 3+}. • Functional RING motif is necessary for As{sup 3+}-induced PML modification.« less
NASA Astrophysics Data System (ADS)
Liu, Jian; Ren, Zhongzhou; Xu, Chang
2018-07-01
Combining the modified Skyrme-like model and the local density approximation model, the slope parameter L of symmetry energy is extracted from the properties of finite nuclei with an improved iterative method. The calculations of the iterative method are performed within the framework of the spherical symmetry. By choosing 200 neutron rich nuclei on 25 isotopic chains as candidates, the slope parameter is constrained to be 50 MeV < L < 62 MeV. The validity of this method is examined by the properties of finite nuclei. Results show that reasonable descriptions on the properties of finite nuclei and nuclear matter can be obtained together.
Dobosz, Marina; Bocci, Chiara; Bonuglia, Margherita; Grasso, Cinzia; Merigioli, Sara; Russo, Alessandra; De Iuliis, Paolo
2010-01-01
Microsatellites have been used for parentage testing and individual identification in forensic science because they are highly polymorphic and show abundant sequences dispersed throughout most eukaryotic nuclear genomes. At present, genetic testing based on DNA technology is used for most domesticated animals, including horses, to confirm identity, to determine parentage, and to validate registration certificates. But if genetic data of one of the putative parents are missing, verifying a genealogy could be questionable. The aim of this paper is to illustrate a new approach to analyze complex cases of disputed relationship with microsatellites markers. These cases were solved by analyzing the genotypes of the offspring and other horses' genotypes in the pedigrees of the putative dam/sire with probabilistic expert systems (PESs). PES was especially efficient in supplying reliable, error-free Bayesian probabilities in complex cases with missing pedigree data. One of these systems was developed for forensic purposes (FINEX program) and is particularly valuable in human analyses. We applied this program to parentage analysis in horses, and we will illustrate how different cases have been successfully worked out.
Stell, W K; Walker, S E; Chohan, K S; Ball, A K
1984-02-01
Antisera to two putative neurotransmitters, luteinizing hormone-releasing hormone (LHRH) and molluscan cardioexcitatory tetrapeptide (H-Phe-Met-Arg-Phe-NH2; FMRF-amide), bind specifically to neurites in the inner nuclear and inner plexiform layers of the goldfish retina. Retrograde labeling showed that intraocular axon terminals originate from the nervus terminalis, whose cell bodies are located in the olfactory nerves. Double immunocytochemical and retrograde labeling showed that some terminalis neurons project to the retina; others may project only within the brain. All terminalis neurons having proven retinal projections were both LHRH- and FMRF-amide-immunoreactive. The activity of retinal ganglion cells was recorded with microelectrodes in isolated superfused goldfish retinas. In ON- and OFF-center double-color-opponent cells, micromolar FMRF-amide and salmon brain gonadotropin-releasing factor ( [Trp7, Leu8] LHRH) caused increased spontaneous activity in the dark, loss of light-induced inhibition, and increased incidence of light-entrained pulsatile response. The nervus terminalis is therefore a putatively peptidergic retinopetal projection. Sex-related olfactory stimuli may act through it, thereby modulating the output of ganglion cells responsive to color contrast.
Human Pif1 helicase unwinds synthetic DNA structures resembling stalled DNA replication forks
George, Tresa; Wen, Qin; Griffiths, Richard; Ganesh, Anil; Meuth, Mark; Sanders, Cyril M.
2009-01-01
Pif-1 proteins are 5′→3′ superfamily 1 (SF1) helicases that in yeast have roles in the maintenance of mitochondrial and nuclear genome stability. The functions and activities of the human enzyme (hPif1) are unclear, but here we describe its DNA binding and DNA remodeling activities. We demonstrate that hPif1 specifically recognizes and unwinds DNA structures resembling putative stalled replication forks. Notably, the enzyme requires both arms of the replication fork-like structure to initiate efficient unwinding of the putative leading replication strand of such substrates. This DNA structure-specific mode of initiation of unwinding is intrinsic to the conserved core helicase domain (hPifHD) that also possesses a strand annealing activity as has been demonstrated for the RecQ family of helicases. The result of hPif1 helicase action at stalled DNA replication forks would generate free 3′ ends and ssDNA that could potentially be used to assist replication restart in conjunction with its strand annealing activity. PMID:19700773
Mookerjee, Shona A; Sia, Elaine A
2006-03-20
The mechanisms that govern mutation avoidance in the mitochondrial genome, though believed to be numerous, are poorly understood. The identification of individual genes has implicated mismatch repair and several recombination pathways in maintaining the fidelity and structural stability of mitochondrial DNA. However, the majority of genes in these pathways have not been identified and the interactions between different pathways have not been extensively studied. Additionally, the multicopy presence of the mitochondrial genome affects the occurrence and persistence of mutant phenotypes, making mitochondrial DNA transmission and sorting important factors affecting mutation accumulation. We present new evidence that the putative recombination genes CCE1, DIN7, and MHR1 have overlapping function with the mismatch repair homolog MSH1 in point mutation avoidance and suppression of aberrant recombination events. In addition, we demonstrate a novel role for Msh1p in mtDNA transmission, a role not predicted by studies of its nuclear homologs.
The importance of genetic verification for determination of Atlantic salmon in north Pacific waters
Nielsen, J.L.; Williams, I.; Sage, G.K.; Zimmerman, C.E.
2003-01-01
Genetic analyses of two unknown but putative Atlantic salmon Salmo salar captured in the Copper River drainage, Alaska, demonstrated the need for validation of morphologically unusual fishes. Mitochondrial DNA sequences (control region and cytochrome b) and data from two nuclear genes [first internal transcribed spacer (ITS-1) sequence and growth hormone (GH1) amplification product] indicated that the fish caught in fresh water on the Martin River was a coho salmon Oncorhynchus kisutch, while the other fish caught in the intertidal zone of the Copper River delta near Grass Island was an Atlantic salmon. Determination of unusual or cryptic fish based on limited physical characteristics and expected seasonal spawning run timing will add to the controversy over farmed Atlantic salmon and their potential effects on native Pacific species. It is clear that determination of all putative collections of Atlantic salmon found in Pacific waters requires validation. Due to uncertainty of fish identification in the field using plastic morphometric characters, it is recommended that genetic analyses be part of the validation process. ?? 2003 The Fisheries Society of the British Isles.
Zeiner, M; Gehring, U
1995-01-01
In search of proteins which interact with activated steroid hormone receptors, we screened a human liver lambda gt11 expression library with the glucocorticoid receptor. We identified and cloned a cDNA sequence of 1322 bp that encodes a protein of 274 aa. This protein consists predominantly of hydrophilic amino acids and contains a putative bipartite nuclear localization signal. The in vitro translated receptor-associating protein runs in SDS/polyacrylamide gels with an apparent molecular mass of 46 kDa. By use of the bacterially expressed fusion protein with glutathione S-transferase we have found that interaction is not limited to the glucocorticoid receptor but included other nuclear receptors--most notably, the estrogen and thyroid receptors. Binding also occurs with the glucocorticoid receptor complexed with the antiglucocorticoid RU 38486, with the estrogen receptor complexed with the antiestrogen 4-hydroxytamoxifen or ICI 164,384, and even with receptors not complexed with ligand. Association with steroid hormone receptors depends on prior receptor activation--i.e., release from heat shock proteins. The sequence identified here appears to be a general partner protein for nuclear hormone receptors, with the gene being expressed in a variety of mammalian tissues. Images Fig. 2 Fig. 3 Fig. 4 PMID:8524784
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2013-07-30
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-07-30
... Generating Station, Units 3 and 4; Southern Nuclear Operating Company; Change to the Primary Sampling System.... The amendment requests to modify the Primary Sampling System (PSS) design, including changes to Tier 1....13-1 ``Primary Sampling System,'' and Subsection 2.3.13, ``Primary Sampling System'' of the Updated...
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2012-06-07
... feet) in height that inundated the Fukushima Dai-ichi nuclear power plant site. The earthquake and... infrastructure and industry in the northeastern coastal areas of Japan. When the earthquake occurred, Fukushima... earthquake appears to have been normal. Following the events at the Fukushima Dai-ichi nuclear power plant...
Large scale obscuration and related climate effects open literature bibliography
DOE Office of Scientific and Technical Information (OSTI.GOV)
Russell, N.A.; Geitgey, J.; Behl, Y.K.
1994-05-01
Large scale obscuration and related climate effects of nuclear detonations first became a matter of concern in connection with the so-called ``Nuclear Winter Controversy`` in the early 1980`s. Since then, the world has changed. Nevertheless, concern remains about the atmospheric effects of nuclear detonations, but the source of concern has shifted. Now it focuses less on global, and more on regional effects and their resulting impacts on the performance of electro-optical and other defense-related systems. This bibliography reflects the modified interest.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-04-24
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Method of storing radioactive wastes using modified tobermorite
Komarneni, Sridhar; Roy, Della M.
1985-01-01
A new cation exchanger is a modified tobermorite containing aluminum isomorphously substituted for silicon and containing sodium or potassium. The exchanger is selective for lead, rubidium, cobalt and cadmium and is selective for cesium over calcium or sodium. The tobermorites are compatable with cement and are useful for the long-term fixation and storage of radioactive nuclear wastes.
Evolving targets for lipid-modifying therapy
Do, Rose Q; Nicholls, Stephen J; Schwartz, Gregory G
2014-01-01
The pathogenesis and progression of atherosclerosis are integrally connected to the concentration and function of lipoproteins in various classes. This review examines existing and emerging approaches to modify low-density lipoprotein and lipoprotein (a), triglyceride-rich lipoproteins, and high-density lipoproteins, emphasizing approaches that have progressed to clinical evaluation. Targeting of nuclear receptors and phospholipases is also discussed. PMID:25172365
Chouhy, Diego; Kocjan, Boštjan J; Staheli, Jeannette P; Bolatti, Elisa M; Hošnjak, Lea; Sagadin, Martin; Giri, Adriana A; Rose, Timothy M; Poljak, Mario
2018-01-01
A modified pan-PV consensus-degenerate hybrid oligonucleotide primer (CODEHOP) PCR was developed for generic and sensitive detection of a broad-spectrum of human papillomaviruses (HPVs) infecting the cutaneous epithelium. To test the analytical sensitivity of the assay we examined 149 eyebrow hair follicle specimens from immunocompetent male patients. HPV DNA was detected in 60 % (89/149) of analysed eyebrow samples with a total of 48 different HPV sequences, representing 21 previously described HPVs and 27 putative novel HPV types. Evidence for ten novel HPV subtypes and seven viral variants, clustering to three out of five genera containing cutaneous HPVs, was also obtained. Thus, we have shown that the modified pan-PV CODEHOP PCR assay is able to identify multiple HPV types, even from different genera, in the same clinical sample. Overall, these results demonstrate that the pan-PV CODEHOP PCR is an excellent tool for screening and identification of novel cutaneous HPVs, even in samples with low viral loads.
Reiman, Eric M
2011-12-01
Alzheimer's disease (AD) is associated with characteristic and progressive reductions in flourodeoxyglucose positron emission tomography (FDG PET) measurements of the regional cerebral metabolic rate for glucose. These reductions begin years before the onset of symptoms, are correlated with clinical severity, and may help predict an affected patient's clinical course and neuropathological diagnosis. Like several other AD biomarkers, FDG PET has the potential to accelerate the evaluation of AD-modifying treatments, particularly in the earliest clinical and preclinical stages. This article considers FDG PET's role in the detection and tracking of AD, its emerging roles in the evaluation of disease-slowing treatments, some of the issues involved in the acquisition, analysis, and interpretation of FDG PET data, and the evidence needed to help qualify FDG PET and other biomarkers for use in the accelerated approval of AD-slowing treatments. It recommends scientific strategies and public policies to further establish the role of FDG PET and other AD biomarkers in therapeutic trials and find demonstrably effective disease-modifying and presymptomatic AD treatments as quickly as possible. Copyright © 2011 Elsevier Inc. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Byrne, Robert T.; Whelan, Fiona; Aller, Pierre
2013-06-01
The putative methyltransferase CmoA is involved in the nucleoside modification of transfer RNA. X-ray crystallography and mass spectrometry are used to show that it contains a novel SAM derivative, S-adenosyl-S-carboxymethyl-l-homocysteine, in which the donor methyl group is replaced by a carboxymethyl group. Uridine at position 34 of bacterial transfer RNAs is commonly modified to uridine-5-oxyacetic acid (cmo{sup 5}U) to increase the decoding capacity. The protein CmoA is involved in the formation of cmo{sup 5}U and was annotated as an S-adenosyl-l-methionine-dependent (SAM-dependent) methyltransferase on the basis of its sequence homology to other SAM-containing enzymes. However, both the crystal structure of Escherichiamore » coli CmoA at 1.73 Å resolution and mass spectrometry demonstrate that it contains a novel cofactor, S-adenosyl-S-carboxymethyl-l-homocysteine (SCM-SAH), in which the donor methyl group is substituted by a carboxymethyl group. The carboxyl moiety forms a salt-bridge interaction with Arg199 that is conserved in a large group of CmoA-related proteins but is not conserved in other SAM-containing enzymes. This raises the possibility that a number of enzymes that have previously been annotated as SAM-dependent are in fact SCM-SAH-dependent. Indeed, inspection of electron density for one such enzyme with known X-ray structure, PDB entry http://scripts.iucr.org/cgi-bin/cr.cgi?rm, suggests that the active site contains SCM-SAH and not SAM.« less
Hall, Kevin W; Eisthen, Heather L; Williams, Barry L
2016-01-01
Pheromones play an important role in modifying vertebrate behavior, especially during courtship and mating. Courtship behavior in urodele amphibians often includes female exposure to secretions from the cloacal gland, as well as other scent glands. The first vertebrate proteinaceous pheromone discovered, the decapeptide sodefrin, is a female attracting pheromone secreted by the cloacal gland of male Cynops pyrrhogaster. Other proteinaceous pheromones in salamanders have been shown to elicit responses from females towards conspecific males. The presence and levels of expression of proteinaceous pheromones have not been identified in the family Ambystomatidae, which includes several important research models. The objective of this research was therefore to identify putative proteinaceous pheromones from male axolotls, Ambystoma mexicanum, as well as their relative expression levels. The results indicate that axolotls possess two different forms of sodefrin precursor-like factor (alpha and beta), as well as a putative ortholog of plethodontid modulating factor. The beta form of sodefrin precursor-like factor was amongst the most highly expressed transcripts within the cloacal gland. The ortholog of plethodontid modulating factor was expressed at a level equivalent to the beta sodefrin precursor-like factor. The results are from a single male axolotl; therefore, we are unable to assess how representative our results may be. Nevertheless, the presence of these highly expressed proteinaceous pheromones suggests that male axolotls use multiple chemical cues to attract female conspecifics. Behavioral assays would indicate whether the putative protein pheromones elicit courtship activity from female axolotls.
Hall, Kevin W.; Eisthen, Heather L.; Williams, Barry L.
2016-01-01
Pheromones play an important role in modifying vertebrate behavior, especially during courtship and mating. Courtship behavior in urodele amphibians often includes female exposure to secretions from the cloacal gland, as well as other scent glands. The first vertebrate proteinaceous pheromone discovered, the decapeptide sodefrin, is a female attracting pheromone secreted by the cloacal gland of male Cynops pyrrhogaster. Other proteinaceous pheromones in salamanders have been shown to elicit responses from females towards conspecific males. The presence and levels of expression of proteinaceous pheromones have not been identified in the family Ambystomatidae, which includes several important research models. The objective of this research was therefore to identify putative proteinaceous pheromones from male axolotls, Ambystoma mexicanum, as well as their relative expression levels. The results indicate that axolotls possess two different forms of sodefrin precursor-like factor (alpha and beta), as well as a putative ortholog of plethodontid modulating factor. The beta form of sodefrin precursor-like factor was amongst the most highly expressed transcripts within the cloacal gland. The ortholog of plethodontid modulating factor was expressed at a level equivalent to the beta sodefrin precursor-like factor. The results are from a single male axolotl; therefore, we are unable to assess how representative our results may be. Nevertheless, the presence of these highly expressed proteinaceous pheromones suggests that male axolotls use multiple chemical cues to attract female conspecifics. Behavioral assays would indicate whether the putative protein pheromones elicit courtship activity from female axolotls. PMID:26885665
Isnard, Amandine; Christian, Jan G.; Kodiha, Mohamed; Stochaj, Ursula; McMaster, W. Robert; Olivier, Martin
2015-01-01
The protease GP63 is an important virulence factor of Leishmania parasites. We previously showed that GP63 reaches the perinuclear area of host macrophages and that it directly modifies nuclear translocation of the transcription factors NF-κB and AP-1. Here we describe for the first time, using molecular biology and in-depth proteomic analyses, that GP63 alters the host macrophage nuclear envelope, and impacts on nuclear processes. Our results suggest that GP63 does not appear to use a classical nuclear localization signal common between Leishmania species for import, but degrades nucleoporins, and is responsible for nuclear transport alterations. In the nucleoplasm, GP63 activity accounts for the degradation and mislocalization of proteins involved amongst others in gene expression and in translation. Collectively, our data indicates that Leishmania infection strongly affects nuclear physiology, suggesting that targeting of nuclear physiology may be a strategy beneficial for virulent Leishmania parasites. PMID:25826301
The effect of music on cognitive performance: insight from neurobiological and animal studies.
Rickard, Nikki S; Toukhsati, Samia R; Field, Simone E
2005-12-01
The past 50 years have seen numerous claims that music exposure enhances human cognitive performance. Critical evaluation of studies across a variety of contexts, however, reveals important methodological weaknesses. The current article argues that an interdisciplinary approach is required to advance this research. A case is made for the use of appropriate animal models to avoid many confounds associated with human music research. Although such research has validity limitations for humans, reductionist methodology enables a more controlled exploration of music's elementary effects. This article also explores candidate mechanisms for this putative effect. A review of neurobiological evidence from human and comparative animal studies confirms that musical stimuli modify autonomic and neurochemical arousal indices, and may also modify synaptic plasticity. It is proposed that understanding how music affects animals provides a valuable conjunct to human research and may be vital in uncovering how music might be used to enhance cognitive performance.
Tammam, Salma N; Azzazy, Hassan M E; Breitinger, Hans G; Lamprecht, Alf
2015-12-07
Many recently discovered therapeutic proteins exert their main function in the nucleus, thus requiring both efficient uptake and correct intracellular targeting. Chitosan nanoparticles (NPs) have attracted interest as protein delivery vehicles due to their biocompatibility and ability to escape the endosomes offering high potential for nuclear delivery. Molecular entry into the nucleus occurs through the nuclear pore complexes, the efficiency of which is dependent on NP size and the presence of nuclear localization sequence (NLS). Chitosan nanoparticles of different sizes (S-NPs ≈ 25 nm; L-NP ≈ 150 nm) were formulated, and they were modified with different densities of the octapeptide NLS CPKKKRKV (S-NPs, 0.25, 0.5, 2.0 NLS/nm(2); L-NPs, 0.6, 0.9, 2 NLS/nm(2)). Unmodified and NLS-tagged NPs were evaluated for their protein loading capacity, extent of cell association, cell uptake, cell surface binding, and finally nuclear delivery efficiency in L929 fibroblasts. To avoid errors generated with cell fractionation and nuclear isolation protocols, nuclear delivery was assessed in intact cells utilizing Förster resonance energy transfer (FRET) fluorometry and microscopy. Although L-NPs showed ≈10-fold increase in protein loading per NP when compared to S-NPs, due to higher cell association and uptake S-NPs showed superior protein delivery. NLS exerts a size and density dependent effect on nanoparticle uptake and surface binding, with a general reduction in NP cell surface binding and an increase in cell uptake with the increase in NLS density (up to 8.4-fold increase in uptake of High-NLS-L-NPs (2 NLS/nm(2)) compared to unmodified L-NPs). However, for nuclear delivery, unmodified S-NPs show higher nuclear localization rates when compared to NLS modified NPs (up to 5-fold by FRET microscopy). For L-NPs an intermediate NLS density (0.9 NLS/nm(2)) seems to provide highest nuclear localization (3.7-fold increase in nuclear delivery compared to High-NLS-L-NPs). Results indicate that a higher NLS density does not result in maximum protein nuclear localization and that a universal optimal density for NPs of different sizes does not exist.
Li, Zicong; He, Xiaoyan; Chen, Liwen; Shi, Junsong; Zhou, Rong; Xu, Weihua
2013-01-01
Abstract The somatic cell nuclear transfer (SCNT) technique has been widely applied to clone pigs or to produce genetically modified pigs. Currently, this technique relies mainly on using terminally differentiated fibroblasts as donor cells. To improve cloning efficiency, only partially differentiated multipotent mesenchymal stem cells (MSCs), thought to be more easily reprogrammed to a pluripotent state, have been used as nuclear donors in pig SCNT. Although in vitro–cultured embryos cloned from porcine MSCs (MSCs-embryos) were shown to have higher preimplantation developmental ability than cloned embryos reconstructed from fibroblasts (Fs-embryos), the difference in in vivo full-term developmental rate between porcine MSCs-embryos and Fs-embryos has not been investigated so far. In this study, we demonstrated that blastocyst total cell number and full-term survival abilities of MSCs-embryos were significantly higher than those of Fs-embryos cloned from the same donor pig. The enhanced developmental potential of MSCs-embryos may be associated with their nuclear donors' DNA methylation profile, because we found that the methylation level of imprinting genes and repeat sequences differed between MSCs and fibroblasts. In addition, we showed that use of transgenic porcine MSCs generated from transgene plasmid transfection as donor cells for SCNT can produce live transgenic cloned pigs. These results strongly suggest that porcine bone marrow MSCs are a desirable donor cell type for production of cloned pigs and genetically modified cloned pigs via SCNT. PMID:24033142
Worldwide advanced nuclear power reactors with passive and inherent safety: What, why, how, and who
DOE Office of Scientific and Technical Information (OSTI.GOV)
Forsberg, C.W.; Reich, W.J.
1991-09-01
The political controversy over nuclear power, the accidents at Three Mile Island (TMI) and Chernobyl, international competition, concerns about the carbon dioxide greenhouse effect and technical breakthroughs have resulted in a segment of the nuclear industry examining power reactor concepts with PRIME safety characteristics. PRIME is an acronym for Passive safety, Resilience, Inherent safety, Malevolence resistance, and Extended time after initiation of an accident for external help. The basic ideal of PRIME is to develop power reactors in which operator error, internal sabotage, or external assault do not cause a significant release of radioactivity to the environment. Several PRIME reactormore » concepts are being considered. In each case, an existing, proven power reactor technology is combined with radical innovations in selected plant components and in the safety philosophy. The Process Inherent Ultimate Safety (PIUS) reactor is a modified pressurized-water reactor, the Modular High Temperature Gas-Cooled Reactor (MHTGR) is a modified gas-cooled reactor, and the Advanced CANDU Project is a modified heavy-water reactor. In addition to the reactor concepts, there is parallel work on super containments. The objective is the development of a passive box'' that can contain radioactivity in the event of any type of accident. This report briefly examines: why a segment of the nuclear power community is taking this new direction, how it differs from earlier directions, and what technical options are being considered. A more detailed description of which countries and reactor vendors have undertaken activities follows. 41 refs.« less
ROSAT PSPC and HRI observations of the composite starburst/Seyfert 2 galaxy NGC 1672
NASA Technical Reports Server (NTRS)
Brandt, W. N.; Halpern, Jules P.; Iwasawa, K.
1995-01-01
The nearby barred spiral galaxy NGC 1672 has been observed with the Position Sensitive Proportional Counter (PSPC) and High Resolution Imager (HRI) instruments on board the ROSAT X-ray satellite. NGC 1672 is thought to have an obscured Seyfert nucleus, and it has strong starburst activity as well. Three bright X-ray sources with luminosities 1-2 x 10(exp 40) erg/s are clearly identified with NGC 1672. The strongest lies at the nucleus, and the other two lie at the ends of NGC 1672's prominent bar, locations that are also bright in H alpha and near-infrared images. The nuclear source is resolved by the HRI on about the scale of the recently identified nuclear ring, and one of the sources at the ends of the bar is also probably resolved. The X-ray spectrum of the nuclear source is quite soft, having a Raymond-Smith plasma temperature of approximately equals 0.7 keV and little evidence for intrinsic absorption. The ROSAT band X-ray flux of the nuclear source appears to be dominated not by X-ray binary emission but rather by diffuse gas emission. The absorption and emission properties of the sources, as well as their spatial extents, lead us to models of superbubbles driven by supernovae. However, the large density and emission measure of the nuclear X-ray source stretch the limits that can be comfortably accommodated by these models. We do not detect direct emission from the putative Seyfert nucleus, although an alternative model for the nuclear source is thermal emission from gas that is photoionized by a hidden Seyfert nucleus. The spectra of the other two X-ray sources are harder than that of the nuclear source, and have similar difficulties with regard to superbubble models.
Patel, Hansa; Truant, Ray; Rachubinski, Richard A; Capone, John P
2005-01-01
Peroxisome proliferator-activated nuclear hormone receptors (PPAR) are ligand-activated transcription factors that play pivotal roles in governing metabolic homeostasis and cell growth. PPARs are primarily in the nucleus but, under certain circumstances, can be found in the cytoplasm. We show here that PPAR(alpha) interacts with the centrosome-associated protein CAP350. CAP350 also interacts with PPAR(delta), PPAR(gamma) and liver-X-receptor alpha, but not with the 9-cis retinoic acid receptor, RXR(alpha). Immunofluorescence analysis indicated that PPAR(alpha) is diffusely distributed in the nucleus and excluded from the cytoplasm. However, in the presence of coexpressed CAP350, PPAR(alpha) colocalizes with CAP350 to discrete nuclear foci and to the centrosome, perinuclear region and intermediate filaments. In contrast, the subcellular distribution of RXR(alpha) or of thyroid hormone receptor alpha was not altered by coexpression of CAP350. An amino-terminal fragment of CAP350 was localized exclusively to nuclear foci and was sufficient to recruit PPAR(alpha) to these sites. Mutation of the single putative nuclear hormone receptor interacting signature motif LXXLL present in this fragment had no effect on its subnuclear localization but abrogated recruitment of PPAR(alpha) to nuclear foci. Surprisingly, mutation of the LXXLL motif in this CAP350 subfragment did not prevent its binding to PPAR(alpha) in vitro, suggesting that this motif serves some function other than PPAR(alpha) binding in recruiting PPAR(alpha) to nuclear spots. CAP350 inhibited PPAR(alpha)-mediated transactivation in an LXXLL-dependent manner, suggesting that CAP350 represses PPAR(alpha) function. Our findings implicate CAP350 in a dynamic process that recruits PPAR(alpha) to discrete nuclear and cytoplasmic compartments and suggest that altered intracellular compartmentalization represents a regulatory process that modulates PPAR function.
Evolution of the nuclear receptor gene superfamily.
Laudet, V; Hänni, C; Coll, J; Catzeflis, F; Stéhelin, D
1992-01-01
Nuclear receptor genes represent a large family of genes encoding receptors for various hydrophobic ligands such as steroids, vitamin D, retinoic acid and thyroid hormones. This family also contains genes encoding putative receptors for unknown ligands. Nuclear receptor gene products are composed of several domains important for transcriptional activation, DNA binding (C domain), hormone binding and dimerization (E domain). It is not known whether these genes have evolved through gene duplication from a common ancestor or if their different domains came from different independent sources. To test these possibilities we have constructed and compared the phylogenetic trees derived from two different domains of 30 nuclear receptor genes. The tree built from the DNA binding C domain clearly shows a common progeny of all nuclear receptors, which can be grouped into three subfamilies: (i) thyroid hormone and retinoic acid receptors, (ii) orphan receptors and (iii) steroid hormone receptors. The tree constructed from the central part of the E domain which is implicated in transcriptional regulation and dimerization shows the same distribution in three subfamilies but two groups of receptors are in a different position from that in the C domain tree: (i) the Drosophila knirps family genes have acquired very different E domains during evolution, and (ii) the vitamin D and ecdysone receptors, as well as the FTZ-F1 and the NGF1B genes, seem to have DNA binding and hormone binding domains belonging to different classes. These data suggest a complex evolutionary history for nuclear receptor genes in which gene duplication events and swapping between domains of different origins took place. PMID:1312460
Federal Register 2010, 2011, 2012, 2013, 2014
2013-10-24
... Nuclear Station, Units 2 and 3; South Carolina Electric and Gas; Changes to the Primary Sampling System... in Fairfield County, South Carolina. The amendment requests to modify the Primary Sampling System..., Figures 2.2.1-1 ``Containment System'' and 2.3.13-1 ``Primary Sampling System,'' and Subsection 2.3.13...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Toth, James J.; Wall, Donald; Wittman, Richard S.
Target assemblies are provided that can include a uranium-comprising annulus. The assemblies can include target material consisting essentially of non-uranium material within the volume of the annulus. Reactors are disclosed that can include one or more discrete zones configured to receive target material. At least one uranium-comprising annulus can be within one or more of the zones. Methods for producing isotopes within target material are also disclosed, with the methods including providing neutrons to target material within a uranium-comprising annulus. Methods for modifying materials within target material are disclosed as well as are methods for characterizing material within a targetmore » material.« less
White, J O; Moore, P A; Elder, M G; Lim, L
1981-01-01
The neonatal administration of testosterone propionate to Wistar rats resulted in anovulatory adults in persistent vaginal oestrus. Clomiphene citrate had a similar effect. In both groups of adults, hyperplasia of the uterine epithelium and occasional metaplasia was observed. The uterine nuclear and cytosol oestrogen and progestin receptors of these anovulatory rats were found to have affinities for their respective ligands similar to those of normal females. The nuclear oestrogen receptor comprised occupied and unoccupied components, as in normal females. The content of the nuclear oestrogen receptor was comparable with that of females in the late dioestrous or pro-oestrous phase. This content was higher in the clomiphene-treated group. Despite the relatively high nuclear oestrogen receptor content the content of progestin receptors, a putative index of the oestrogenic response, was lower in the treated rats than in normal adult females throughout the cycle. Administration of oestradiol to both treatment groups resulted in depletion of cytosol oestrogen receptor content 1 h later, which, however, was not reflected by an increase in the content of nuclear oestrogen receptors. There was no measurable increase in progesterone receptor content in treated rats after daily administration of oestrogen (5 microgram/rat) for 3 days. These changes in sex-hormone-receptor interactions involving an impairment of the normal oestrogenic response may be associated with the abnormal differentiation of the uterus in these sterile, anovulatory animals. Images Fig. 1. Fig. 2. PMID:7316994
Genome-wide screen uncovers novel pathways for tRNA processing and nuclear–cytoplasmic dynamics
Wu, Jingyan; Bao, Alicia; Chatterjee, Kunal; Wan, Yao; Hopper, Anita K.
2015-01-01
Transfer ribonucleic acids (tRNAs) are essential for protein synthesis. However, key gene products involved in tRNA biogenesis and subcellular movement remain to be discovered. We conducted the first comprehensive unbiased analysis of the role of nearly an entire proteome in tRNA biology and describe 162 novel and 12 previously known Saccharomyces cerevisiae gene products that function in tRNA processing, turnover, and subcellular movement. tRNA nuclear export is of particular interest because it is essential, but the known tRNA exporters (Los1 [exportin-t] and Msn5 [exportin-5]) are unessential. We report that mutations of CRM1 (Exportin-1), MEX67/MTR2 (TAP/p15), and five nucleoporins cause accumulation of unspliced tRNA, a hallmark of defective tRNA nuclear export. CRM1 mutation genetically interacts with los1Δ and causes altered tRNA nuclear–cytoplasmic distribution. The data implicate roles for the protein and mRNA nuclear export machineries in tRNA nuclear export. Mutations of genes encoding actin cytoskeleton components and mitochondrial outer membrane proteins also cause accumulation of unspliced tRNA, likely due to defective splicing on mitochondria. Additional gene products, such as chromatin modification enzymes, have unanticipated effects on pre-tRNA end processing. Thus, this genome-wide screen uncovered putative novel pathways for tRNA nuclear export and extensive links between tRNA biology and other aspects of cell physiology. PMID:26680305
Stimson, E; Virji, M; Barker, S; Panico, M; Blench, I; Saunders, J; Payne, G; Moxon, E R; Dell, A; Morris, H R
1996-01-01
Pili, which are filamentous protein structures on the surface of the meningitis-causing organism Neisseria meningitidis, are known to be post-translationally modified with substituents that affect their mobility in SDS/PAGE and which might play a crucial role in adherence and bloodstream invasion. Tryptic digests of pili were analysed by fast atom bombardment and electrospray MS to identify putative modifications. Serine-93 was found to carry a novel modification of alpha-glycerophosphate. This is the first time that alpha-glycerophosphate has been observed as a substituent of a prokaryotic or eukaryotic protein. PMID:8645220
Germline modification of domestic animals
Tang, L.; González, R.; Dobrinski, I.
2016-01-01
Genetically-modified domestic animal models are of increasing significance in biomedical research and agriculture. As authentic ES cells derived from domestic animals are not yet available, the prevailing approaches for engineering genetic modifications in those animals are pronuclear microinjection and somatic cell nuclear transfer (SCNT, also known as cloning). Both pronuclear microinjection and SCNT are inefficient, costly, and time-consuming. In animals produced by pronuclear microinjection, the exogenous transgene is usually inserted randomly into the genome, which results in highly variable expression patterns and levels in different founders. Therefore, significant efforts are required to generate and screen multiple founders to obtain animals with optimal transgene expression. For SCNT, specific genetic modifications (both gain-of-function and loss-of-function) can be engineered and carefully selected in the somatic cell nucleus before nuclear transfer. SCNT has been used to generate a variety of genetically modified animals such as goats, pigs, sheep and cattle; however, animals resulting from SCNT frequently suffer from developmental abnormalities associated with incomplete nuclear reprogramming. Other strategies to generate genetically-modified animals rely on the use of the spermatozoon as a natural vector to introduce genetic material into the female gamete. This sperm mediated DNA transfer (SMGT) combined with intracytoplasmatic sperm injection (ICSI) has relatively high efficiency and allows the insertion of large DNA fragments, which, in turn, enhance proper gene expression. An approach currently being developed to complement SCNT for producing genetically modified animals is germ cell transplantation using genetically modified male germline stem cells (GSCs). This approach relies on the ability of GSCs that are genetically modified in vitro to colonize the recipient testis and produce donor derived sperm upon transplantation. As the genetic change is introduced into the male germ line just before the onset of spermatogenesis, the time required for the production of genetically modified sperm is significantly shorter using germ cell transplantation compared to cloning or embryonic stem (ES) cell based technology. Moreover, the GSC-mediated germline modification circumvents problems associated with embryo manipulation and nuclear reprogramming. Currently, engineering targeted mutations in domestic animals using GSCs remains a challenge as GSCs from those animals are difficult to maintain in vitro for an extended period of time. Recent advances in genome editing techniques such as Zinc-Finger Nucleases (ZFNs), Transcription Activator-like Effector Nucleases (TALENs) and Clustered Regularly Interspaced Short Palindromic Repeats (CRISPRs) greatly enhance the efficiency of engineering targeted genetic change in domestic animals as demonstrated by the generation of several gene knock-out pig and cattle models using those techniques. The potential of GSC-mediated germline modification in making targeted genetic modifications in domestic animal models will be maximized if those genome editing techniques can be applied in GSCs. PMID:27390591
Burr, Tom; Hamada, Michael S.; Ticknor, Larry; ...
2015-01-01
The aim of nuclear safeguards is to ensure that special nuclear material is used for peaceful purposes. Historically, nuclear material accounting (NMA) has provided the quantitative basis for monitoring for nuclear material loss or diversion, and process monitoring (PM) data is collected by the operator to monitor the process. PM data typically support NMA in various ways, often by providing a basis to estimate some of the in-process nuclear material inventory. We develop options for combining PM residuals and NMA residuals (residual = measurement - prediction), using a hybrid of period-driven and data-driven hypothesis testing. The modified statistical tests canmore » be used on time series of NMA residuals (the NMA residual is the familiar material balance), or on a combination of PM and NMA residuals. The PM residuals can be generated on a fixed time schedule or as events occur.« less
Production of Synthetic Nuclear Melt Glass
Molgaard, Joshua J.; Auxier, John D.; Giminaro, Andrew V.; Oldham, Colton J.; Gill, Jonathan; Hall, Howard L.
2016-01-01
Realistic surrogate nuclear debris is needed within the nuclear forensics community to test and validate post-detonation analysis techniques. Here we outline a novel process for producing bulk surface debris using a high temperature furnace. The material developed in this study is physically and chemically similar to trinitite (the melt glass produced by the first nuclear test). This synthetic nuclear melt glass is assumed to be similar to the vitrified material produced near the epicenter (ground zero) of any surface nuclear detonation in a desert environment. The process outlined here can be applied to produce other types of nuclear melt glass including that likely to be formed in an urban environment. This can be accomplished by simply modifying the precursor matrix to which this production process is applied. The melt glass produced in this study has been analyzed and compared to trinitite, revealing a comparable crystalline morphology, physical structure, void fraction, and chemical composition. PMID:26779720
Nuclear Forensics and Radiochemistry: Reaction Networks
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rundberg, Robert S.
In the intense neutron flux of a nuclear explosion the production of isotopes may occur through successive neutron induced reactions. The pathway to these isotopes illustrates both the complexity of the problem and the need for high quality nuclear data. The growth and decay of radioactive isotopes can follow a similarly complex network. The Bateman equation will be described and modified to apply to the transmutation of isotopes in a high flux reactor. A alternative model of growth and decay, the GD code, that can be applied to fission products will also be described.
Teasdale, Luisa C; Köhler, Frank; Murray, Kevin D; O'Hara, Tim; Moussalli, Adnan
2016-09-01
The qualification of orthology is a significant challenge when developing large, multiloci phylogenetic data sets from assembled transcripts. Transcriptome assemblies have various attributes, such as fragmentation, frameshifts and mis-indexing, which pose problems to automated methods of orthology assessment. Here, we identify a set of orthologous single-copy genes from transcriptome assemblies for the land snails and slugs (Eupulmonata) using a thorough approach to orthology determination involving manual alignment curation, gene tree assessment and sequencing from genomic DNA. We qualified the orthology of 500 nuclear, protein-coding genes from the transcriptome assemblies of 21 eupulmonate species to produce the most complete phylogenetic data matrix for a major molluscan lineage to date, both in terms of taxon and character completeness. Exon capture targeting 490 of the 500 genes (those with at least one exon >120 bp) from 22 species of Australian Camaenidae successfully captured sequences of 2825 exons (representing all targeted genes), with only a 3.7% reduction in the data matrix due to the presence of putative paralogs or pseudogenes. The automated pipeline Agalma retrieved the majority of the manually qualified 500 single-copy gene set and identified a further 375 putative single-copy genes, although it failed to account for fragmented transcripts resulting in lower data matrix completeness when considering the original 500 genes. This could potentially explain the minor inconsistencies we observed in the supported topologies for the 21 eupulmonate species between the manually curated and 'Agalma-equivalent' data set (sharing 458 genes). Overall, our study confirms the utility of the 500 gene set to resolve phylogenetic relationships at a range of evolutionary depths and highlights the importance of addressing fragmentation at the homolog alignment stage for probe design. © 2016 John Wiley & Sons Ltd.
Montelongo, Tinguaro; Gómez-Zurita, Jesús
2015-01-01
Many unisexual animal lineages supposedly arose from hybridization. However, support for their putative hybrid origins mostly comes from indirect methodologies, which are rarely confirmatory. Here we provide compelling data indicating that tetraploid unisexual Calligrapha are true genetic mosaics obtained via analysis of mitochondrial DNA (mtDNA) and allelic variation and coalescence times for three single-copy nuclear genes (CPS, HARS, and Wg) in five of six unisexual Calligrapha and a representative sample of bisexual species. Nuclear allelic diversity in unisexuals consistently segregates in the gene pools of at least two but up to three divergent bisexual species, interpreted as putative parentals of interspecific hybridization crosses. Interestingly, their mtDNA diversity derives from an additional yet undiscovered older evolutionary lineage that is possibly the same for all independently originated unisexual species. One possibly extinct species transferred its mtDNA to several evolutionary lineages in a wave of hybridization events during the Pliocene, whereby descendant species retained a polymorphic mtDNA constitution. Recent hybridizations, in the Pleistocene and always involving females with the old introgressed mtDNA, seemingly occurred in the lineages leading to unisexual species, decoupling mtDNA introgression (and inferences derived from these data, such as timing and parentage) from subsequent acquisition of the new reproductive mode. These results illuminate an unexpected complexity in possible routes to animal unisexuality, with implications for the interpretation of ancient unisexuality. If the origin of unisexuality requires a mechanism where (1) hybridization is a necessary but insufficient condition and (2) multiple bouts of hybridization involving more than two divergent lineages are required, then the origins of several classical unisexual systems may have to be reassessed.
A cysteine protease encoded by the baculovirus Bombyx mori nuclear polyhedrosis virus.
Ohkawa, T; Majima, K; Maeda, S
1994-01-01
Sequence analysis of the BamHI F fragment of the genome of Bombyx mori nuclear polyhedrosis virus (BmNPV) revealed an open reading frame whose deduced amino acid sequence had homology to those of cysteine proteases of the papain superfamily. The putative cysteine protease sequence (BmNPV-CP) was 323 amino acids long and showed 35% identity to a cysteine proteinase precursor from Trypanosoma brucei. Of 36 residues conserved among cathepsins B, H, L, and S and papain, 31 were identical in BmNPV-CP. In order to determine the activity and function of the putative cysteine protease, a BmNPV mutant (BmCysPD) was constructed by homologous recombination of the protease gene with a beta-galactosidase gene cassette. BmCysPD-infected BmN cell extracts were significantly reduced in acid protease activity compared with wild-type virus-infected cell extracts. The cysteine protease inhibitor E-64 [trans-epoxysuccinylleucylamido-(4-guanidino)butane] inhibited wild-type virus-expressed protease activity. Deletion of the cysteine protease gene had no significant effect on viral growth or polyhedron production in BmN cells, indicating that the cysteine protease was not essential for viral replication in vitro. However, B. mori larvae infected with BmCysPD showed symptoms different from those of wild-type BmNPV-infected larvae, e.g., less degradation of the body, including fat body cells, white body surface color due presumably to undegraded epidermal cells, and an increase in the number of polyhedra released into the hemolymph. This is the first report of (i) a virus-encoded protease with activity on general substrates and (ii) evidence that a virus-encoded protease may play a role in degradation of infected larvae to facilitate horizontal transmission of the virus. Images PMID:8083997
Rutschmann, Sereina; Detering, Harald; Simon, Sabrina; Funk, David H; Gattolliat, Jean-Luc; Hughes, Samantha J; Raposeiro, Pedro M; DeSalle, Rob; Sartori, Michel; Monaghan, Michael T
2017-02-01
The study of processes driving diversification requires a fully sampled and well resolved phylogeny, although a lack of phylogenetic markers remains a limitation for many non-model groups. Multilocus approaches to the study of recent diversification provide a powerful means to study the evolutionary process, but their application remains restricted because multiple unlinked loci with suitable variation for phylogenetic or coalescent analysis are not available for most non-model taxa. Here we identify novel, putative single-copy nuclear DNA (nDNA) phylogenetic markers to study the colonization and diversification of an aquatic insect species complex, Cloeon dipterum L. 1761 (Ephemeroptera: Baetidae), in Macaronesia. Whole-genome sequencing data from one member of the species complex were used to identify 59 nDNA loci (32,213 base pairs), followed by Sanger sequencing of 29 individuals sampled from 13 islands of three Macaronesian archipelagos. Multispecies coalescent analyses established six putative species. Three island species formed a monophyletic clade, with one species occurring on the Azores, Europe and North America. Ancestral state reconstruction indicated at least two colonization events from the mainland (to the Canaries, respectively Azores) and one within the archipelago (between Madeira and the Canaries). Random subsets of the 59 loci showed a positive linear relationship between number of loci and node support. In contrast, node support in the multispecies coalescent tree was negatively correlated with mean number of phylogenetically informative sites per locus, suggesting a complex relationship between tree resolution and marker variability. Our approach highlights the value of combining genomics, coalescent-based phylogeography, species delimitation, and phylogenetic reconstruction to resolve recent diversification events in an archipelago species complex. Copyright © 2016 Elsevier Inc. All rights reserved.
Alvares, Keith; Dixit, Saryu N; Lux, Elizabeth; Veis, Arthur
2009-09-18
Studies of mineralization of embryonic spicules and of the sea urchin genome have identified several putative mineralization-related proteins. These predicted proteins have not been isolated or confirmed in mature mineralized tissues. Mature Lytechinus variegatus teeth were demineralized with 0.6 N HCl after prior removal of non-mineralized constituents with 4.0 M guanidinium HCl. The HCl-extracted proteins were fractionated on ceramic hydroxyapatite and separated into bound and unbound pools. Gel electrophoresis compared the protein distributions. The differentially present bands were purified and digested with trypsin, and the tryptic peptides were separated by high pressure liquid chromatography. NH2-terminal sequences were determined by Edman degradation and compared with the genomic sequence bank data. Two of the putative mineralization-related proteins were found. Their complete amino acid sequences were cloned from our L. variegatus cDNA library. Apatite-binding UTMP16 was found to be present in two isoforms; both isoforms had a signal sequence, a Ser-Asp-rich extracellular matrix domain, and a transmembrane and cytosolic insertion sequence. UTMP19, although rich in Glu and Thr did not bind to apatite. It had neither signal peptide nor transmembrane domain but did have typical nuclear localization and nuclear exit signal sequences. Both proteins were phosphorylated and good substrates for phosphatase. Immunolocalization studies with anti-UTMP16 show it to concentrate at the syncytial membranes in contact with the mineral. On the basis of our TOF-SIMS analyses of magnesium ion and Asp mapping of the mineral phase composition, we speculate that UTMP16 may be important in establishing the high magnesium columns that fuse the calcite plates together to enhance the mechanical strength of the mineralized tooth.
Vartanian, Jean-Pierre; Wain-Hobson, Simon
2002-05-28
Nuclear mtDNA sequences (numts) are a widespread family of paralogs evolving as pseudogenes in chromosomal DNA [Zhang, D. E. & Hewitt, G. M. (1996) TREE 11, 247-251 and Bensasson, D., Zhang, D., Hartl, D. L. & Hewitt, G. M. (2001) TREE 16, 314-321]. When trying to identify the species origin of an unknown DNA sample by way of an mtDNA locus, PCR may amplify both mtDNA and numts. Indeed, occasionally numts dominate confounding attempts at species identification [Bensasson, D., Zhang, D. X. & Hewitt, G. M. (2000) Mol. Biol. Evol. 17, 406-415; Wallace, D. C., et al. (1997) Proc. Natl. Acad. Sci. USA 94, 14900-14905]. Rhesus and cynomolgus macaque mtDNA haplotypes were identified in a study of oral polio vaccine samples dating from the late 1950s [Blancou, P., et al. (2001) Nature (London) 410, 1045-1046]. They were accompanied by a number of putative numts. To confirm that these putative numts were of macaque origin, a library of numts corresponding to a small segment of 12S rDNA locus has been made by using DNA from a Chinese rhesus macaque. A broad distribution was found with up to 30% sequence variation. Phylogenetic analysis showed that the evolutionary trajectories of numts and bona fide mtDNA haplotypes do not overlap with the signal exception of the host species; mtDNA fragments are continually crossing over into the germ line. In the case of divergent mtDNA sequences from old oral polio vaccine samples [Blancou, P., et al. (2001) Nature (London) 410, 1045-1046], all were closely related to numts in the Chinese macaque library.
León-Del-Río, Alfonso; Valadez-Graham, Viviana; Gravel, Roy A
2017-08-21
The vitamin biotin is an essential nutrient for the metabolism and survival of all organisms owing to its function as a cofactor of enzymes collectively known as biotin-dependent carboxylases. These enzymes use covalently attached biotin as a vector to transfer a carboxyl group between donor and acceptor molecules during carboxylation reactions. In human cells, biotin-dependent carboxylases catalyze key reactions in gluconeogenesis, fatty acid synthesis, and amino acid catabolism. Biotin is attached to apocarboxylases by a biotin ligase: holocarboxylase synthetase (HCS) in mammalian cells and BirA in microbes. Despite their evolutionary distance, these proteins share structural and sequence similarities, underscoring their importance across all life forms. However, beyond its role in metabolism, HCS participates in the regulation of biotin utilization and acts as a nuclear transcriptional coregulator of gene expression. In this review, we discuss the function of HCS and biotin in metabolism and human disease, a putative role for the enzyme in histone biotinylation, and its participation as a nuclear factor in chromatin dynamics. We suggest that HCS be classified as a moonlighting protein, with two biotin-dependent cytosolic metabolic roles and a distinct biotin-independent nuclear coregulatory function.
Modular structural elements in the replication origin region of Tetrahymena rDNA.
Du, C; Sanzgiri, R P; Shaiu, W L; Choi, J K; Hou, Z; Benbow, R M; Dobbs, D L
1995-01-01
Computer analyses of the DNA replication origin region in the amplified rRNA genes of Tetrahymena thermophila identified a potential initiation zone in the 5'NTS [Dobbs, Shaiu and Benbow (1994), Nucleic Acids Res. 22, 2479-2489]. This region consists of a putative DNA unwinding element (DUE) aligned with predicted bent DNA segments, nuclear matrix or scaffold associated region (MAR/SAR) consensus sequences, and other common modular sequence elements previously shown to be clustered in eukaryotic chromosomal origin regions. In this study, two mung bean nuclease-hypersensitive sites in super-coiled plasmid DNA were localized within the major DUE-like element predicted by thermodynamic analyses. Three restriction fragments of the 5'NTS region predicted to contain bent DNA segments exhibited anomalous migration characteristic of bent DNA during electrophoresis on polyacrylamide gels. Restriction fragments containing the 5'NTS region bound Tetrahymena nuclear matrices in an in vitro binding assay, consistent with an association of the replication origin region with the nuclear matrix in vivo. The direct demonstration in a protozoan origin region of elements previously identified in Drosophila, chick and mammalian origin regions suggests that clusters of modular structural elements may be a conserved feature of eukaryotic chromosomal origins of replication. Images PMID:7784181
Conservation of Matrix Attachment Region-Binding Filament-Like Protein 1 among Higher Plants1
Harder, Patricia A.; Silverstein, Rebecca A.; Meier, Iris
2000-01-01
The interaction of chromatin with the nuclear matrix via matrix attachment regions (MARs) on the DNA is considered to be of fundamental importance for higher-order chromatin organization and the regulation of gene expression. We have previously isolated a novel nuclear matrix-localized protein (MFP1) from tomato (Lycopersicon esculentum) that preferentially binds to MAR DNA. Tomato MFP1 has a predicted filament-protein-like structure and is associated with the nuclear envelope via an N-terminal targeting domain. Based on the antigenic relationship, we report here that MFP1 is conserved in a large number of dicot and monocot species. Several cDNAs were cloned from tobacco (Nicotiana tabacum) and shown to correspond to two tobacco MFP1 genes. Comparison of the primary and predicted secondary structures of MFP1 from tomato, tobacco, and Arabidopsis indicates a high degree of conservation of the N-terminal targeting domain, the overall putative coiled-coil structure of the protein, and the C-terminal DNA-binding domain. In addition, we show that tobacco MFP1 is regulated in an organ-specific and developmental fashion, and that this regulation occurs at the level of transcription or RNA stability. PMID:10631266
Ploidy Levels among Species in the ‘Oxalis tuberosa Alliance’ as Inferred by Flow Cytometry
EMSHWILLER, EVE
2002-01-01
The ‘Oxalis tuberosa alliance’ is a group of Andean Oxalis species allied to the Andean tuber crop O. tuberosa Molina (Oxalidaceae), commonly known as ‘oca’. As part of a larger project studying the origins of polyploidy and domestication of cultivated oca, flow cytometry was used to survey DNA ploidy levels among Bolivian and Peruvian accessions of alliance members. In addition, this study provided a first assessment of C‐values in the alliance by estimating nuclear DNA contents of these accessions using chicken erythrocytes as internal standard. Ten Bolivian accessions of cultivated O. tuberosa were confirmed to be octoploid, with a mean nuclear DNA content of approx. 3·6 pg/2C. Two Peruvian wild Oxalis species, O. phaeotricha and O. picchensis, were inferred to be tetraploid (both with approx. 1·67 pg/2C), the latter being one of the putative progenitors of O. tuberosa identified by chloroplast‐expressed glutamine synthetase data in prior work. The remaining accessions (from 78 populations provisionally identified as 35 species) were DNA diploid, with nuclear DNA contents varying from 0·79 to 1·34 pg/2C. PMID:12102530
Improvements to the nuclear model code GNASH for cross section calculations at higher energies
DOE Office of Scientific and Technical Information (OSTI.GOV)
Young, P.G.; Chadwick, M.B.
1994-05-01
The nuclear model code GNASH, which in the past has been used predominantly for incident particle energies below 20 MeV, has been modified extensively for calculations at higher energies. The model extensions and improvements are described in this paper, and their significance is illustrated by comparing calculations with experimental data for incident energies up to 160 MeV.
Mapping Nuclear Fallout Using the Weather Research & Forecasting (WRF) Model
2012-09-01
relevant modules, originally designed to predict the settling of volcanic ash, such that a stabilized cloud of nuclear particulate is initialized...within the model. This modified code is then executed for various atmospheric test explosions and the results are qualitatively and quantitatively...HYSPLIT Simulation ....................................... 44 Figure 7. WRF Fallout Prediction for Test Shot George, 0.8 R/h at H+1
Federal Register 2010, 2011, 2012, 2013, 2014
2012-06-07
... Fukushima Dai-ichi nuclear power plant in March 2011. Order EA-12-051 requires all licensees and... complying with Order EA-12-051. Following the events at the Fukushima Dai-ichi nuclear power plant, the NRC... agency should make additional improvements to these programs in light of the events at Fukushima Dai-ichi...
Senturk, Vesile; Abas, Melanie; Berksun, Oguz; Stewart, Robert
2011-03-24
Social support is strongly implicated in the aetiology of perinatal mental disorder: particularly the quality of the marital and family environment. Family structures are important under-researched potential modifiers. Turkey offers particular advantages for research in this area because of long-standing coexistence of Western and Middle Eastern family structures. We aimed to investigate associations between the quality of key relationships and depression in women in their third trimester of pregnancy, and the extent to which these associations were modified by family structure. Women attending antenatal clinics in their third trimester were recruited from urban and rural settings in Ankara. A nuclear family structure was defined as a wife and husband living alone or with their children in the same household, whereas a traditional/extended family structure was defined if another adult was living with the married couple in the same household. Depression was ascertained using the Edinburgh Postnatal Depression Scale (EPDS) and social support was assessed by the Close Person Questionnaire with respect to the husband, mother and mother-in-law. Social support was compared between participants with/without case-level depression on the EPDS in linear regression models adjusted for relevant covariates, then stratified by nuclear/traditional family structure. Of 772 women approached, 751 (97.3%) participated and 730 (94.6%) had sufficient data for this analysis. Prevalence of case-level depression was 33.1% and this was associated with lower social support from all three family members but not with traditional/nuclear family structure. The association between depression and lower emotional support from the husband was significantly stronger in traditional compared to nuclear family environments. Lower quality of relationships between key family members was strongly associated with third trimester depression. Family structure modified the association but, contrary to expectations, spousal emotional support was a stronger correlate of antenatal depression in traditional rather than nuclear family settings. Previous psychiatric history was not formally ascertained and the temporal relationship between mood state and social support needs to be clarified. © 2011 Senturk et al; licensee BioMed Central Ltd.
Deacon, Nicholas John; Grossman, Jake Joseph; Schweiger, Anna Katharina; Armour, Isabella; Cavender-Bares, Jeannine
2017-12-01
Aspen groves along the Niobrara River in Nebraska have long been a biogeographic curiosity due to morphological differences from nearby remnant Populus tremuloides populations. Pleistocene hybridization between P. tremuloides and P. grandidentata has been proposed, but the nearest P. grandidentata populations are currently several hundred kilometers east. We tested the hybrid-origin hypothesis using genetic data and characterized putative hybrids phenotypically. We compared nuclear microsatellite loci and chloroplast sequences of Niobrara River aspens to their putative parental species. Parental species and putative hybrids were also grown in a common garden for phenotypic comparison. On the common garden plants, we measured leaf morphological traits and leaf-level spectral reflectance profiles, from which chemical traits were derived. The genetic composition of the three unique Niobrara aspen genotypes is consistent with the hybridization hypothesis and with maternal chloroplast inheritance from P. grandidentata . Leaf margin dentition and abaxial pubescence differentiated taxa, with the hybrids showing intermediate values. Spectral profiles allowed statistical separation of taxa in short-wave infrared wavelengths, with hybrids showing intermediate values, indicating that traits associated with internal structure of leaves and water absorption may vary among taxa. However, reflectance values in the visible region did not differentiate taxa, indicating that traits related to pigments are not differentiated. Both genetic and phenotypic results support the hypothesis of a hybrid origin for these genetically unique aspens. However, low genetic diversity and ongoing ecological and climatic threats to the hybrid taxon present a challenge for conservation of these relictual boreal communities. © 2017 Botanical Society of America.
DNA binding of the p21 repressor ZBTB2 is inhibited by cytosine hydroxymethylation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lafaye, Céline; Barbier, Ewa; Miscioscia, Audrey
2014-03-28
Highlights: • 5-hmC epigenetic modification is measurable in HeLa, SH-SY5Y and UT7-MPL cell lines. • ZBTB2 binds to DNA probes containing 5-mC but not to sequences containing 5-hmC. • This differential binding is verified with DNA sequences involved in p21 regulation. - Abstract: Recent studies have demonstrated that the modified base 5-hydroxymethylcytosine (5-hmC) is detectable at various rates in DNA extracted from human tissues. This oxidative product of 5-methylcytosine (5-mC) constitutes a new and important actor of epigenetic mechanisms. We designed a DNA pull down assay to trap and identify nuclear proteins bound to 5-hmC and/or 5-mC. We applied thismore » strategy to three cancerous cell lines (HeLa, SH-SY5Y and UT7-MPL) in which we also measured 5-mC and 5-hmC levels by HPLC-MS/MS. We found that the putative oncoprotein Zinc finger and BTB domain-containing protein 2 (ZBTB2) is associated with methylated DNA sequences and that this interaction is inhibited by the presence of 5-hmC replacing 5-mC. As published data mention ZBTB2 recognition of p21 regulating sequences, we verified that this sequence specific binding was also alleviated by 5-hmC. ZBTB2 being considered as a multifunctional cell proliferation activator, notably through p21 repression, this work points out new epigenetic processes potentially involved in carcinogenesis.« less
Maniar, Jay M.; Fire, Andrew Z.
2011-01-01
SUMMARY Background The development of the germline in Caenorhabditis elegans is a complex process involving the regulation of thousands of genes in a coordinated manner. Several genes required for small RNA biogenesis and function are among those required for the proper organization of the germline. EGO-1 is a putative RNA-directed RNA polymerase (RdRP) that is required for multiple aspects of C. elegans germline development and efficient RNAi of germline-expressed genes. RdRPs have been proposed to act through a variety of mechanisms including the post-transcriptional targeting of specific mRNAs as well as through a direct interaction with chromatin. Despite extensive investigation, the molecular role of EGO-1 has remained enigmatic. Results Here we use high-throughput small RNA and messenger RNA sequencing to investigate EGO-1 function. We found that EGO-1 is required to produce a distinct pool of small RNAs antisense to a number of germline-expressed mRNAs through several developmental stages. These potential mRNA targets fall into distinct classes, including genes required for kinetochore and nuclear pore assembly, histone-modifying activities and centromeric proteins. We also found several RNAi-related genes to be targets of EGO-1. Finally, we show a strong association between the loss of small RNAs and the rise of mRNA levels in ego-1(−) animals. Conclusions Our data support the conclusion that EGO-1 produces triphosphorylated small RNAs derived from mRNA templates and that these small RNAs modulate gene expression through the targeting of their cognate mRNAs. PMID:21396820
Schetter, Aaron; Askjaer, Peter; Piano, Fabio; Mattaj, Iain; Kemphues, Kenneth
2006-01-01
Nucleoporins are components of the nuclear pore, which is required for nucleo-cytoplasmic transport. We report a role for a subclass of nucleoporins in orienting the mitotic spindle in C. elegans embryos. RNAi-mediated depletion of any of five putative nucleoporins npp-1, npp-3, npp-4, npp-11, and npp-13 leads to indistinguishable spindle orientation defects. Transgenic worms expressing NPP-1::GFP or NPP-11::GFP show GFP localization at the nuclear envelope, consistent with their predicted function. NPP-1 interacts with the other nucleoporins in yeast two-hybrid assays suggesting that the proteins affect spindle orientation by a common process. The failed orientation phenotype of npp-1(RNAi) is at least partially epistatic to the ectopic spindle rotation in the AB blastomere of par-3 mutant embryos. This suggests that NPP-1 contributes to the mechanics of spindle orientation. However, NPP-1 is also required for PAR-6 asymmetry at the two-cell stage, indicating that nucleoporins may be required to define cortical domains in the germ line blasotmere P1. Nuclear envelope structure is abnormal in npp-1(RNAi) embryos but the envelope maintains its integrity and most nuclear proteins we assayed accumulate normally. These findings raise the possibility that these nucleoporins may have direct roles in orienting the mitotic spindle and the maintenance of cell polarity. PMID:16325795
Vegetative hyphal fusion and subsequent nuclear behavior in Epichloë grass endophytes.
Shoji, Jun-Ya; Charlton, Nikki D; Yi, Mihwa; Young, Carolyn A; Craven, Kelly D
2015-01-01
Epichloë species (including the former genus Neotyphodium) are fungal symbionts of many agronomically important forage grasses, and provide their grass hosts with protection from a wide range of biotic and abiotic stresses. Epichloë species include many interspecific hybrids with allodiploid-like genomes, which may provide the potential for combined traits or recombination to generate new traits. Though circumstantial evidence suggests that such interspecific hybrids might have arisen from nuclear fusion events following vegetative hyphal fusion between different Epichloë strains, this hypothesis has not been addressed empirically. Here, we investigated vegetative hyphal fusion and subsequent nuclear behavior in Epichloë species. A majority of Epichloë strains, especially those having a sexual stage, underwent self vegetative hyphal fusion. Vegetative fusion also occurred between two hyphae from different Epichloë strains. Though Epichloë spp. are uninucleate fungi, hyphal fusion resulted in two nuclei stably sharing the same cytoplasm, which might ultimately lead to nuclear fusion. In addition, protoplast fusion experiments gave rise to uninucleate putative hybrids, which apparently had two markers, one from each parent within the same nucleus. These results are consistent with the notion that interspecific hybrids arise from vegetative hyphal fusion. However, we also discuss additional factors, such as post-hybridization selection, that may be important to explain the recognized prevalence of hybrids in Epichloë species.
Vegetative Hyphal Fusion and Subsequent Nuclear Behavior in Epichloë Grass Endophytes
Shoji, Jun-ya; Charlton, Nikki D.; Yi, Mihwa; Young, Carolyn A.; Craven, Kelly D.
2015-01-01
Epichloë species (including the former genus Neotyphodium) are fungal symbionts of many agronomically important forage grasses, and provide their grass hosts with protection from a wide range of biotic and abiotic stresses. Epichloë species include many interspecific hybrids with allodiploid-like genomes, which may provide the potential for combined traits or recombination to generate new traits. Though circumstantial evidence suggests that such interspecific hybrids might have arisen from nuclear fusion events following vegetative hyphal fusion between different Epichloë strains, this hypothesis has not been addressed empirically. Here, we investigated vegetative hyphal fusion and subsequent nuclear behavior in Epichloë species. A majority of Epichloë strains, especially those having a sexual stage, underwent self vegetative hyphal fusion. Vegetative fusion also occurred between two hyphae from different Epichloë strains. Though Epichloë spp. are uninucleate fungi, hyphal fusion resulted in two nuclei stably sharing the same cytoplasm, which might ultimately lead to nuclear fusion. In addition, protoplast fusion experiments gave rise to uninucleate putative hybrids, which apparently had two markers, one from each parent within the same nucleus. These results are consistent with the notion that interspecific hybrids arise from vegetative hyphal fusion. However, we also discuss additional factors, such as post-hybridization selection, that may be important to explain the recognized prevalence of hybrids in Epichloë species. PMID:25837972
Godinho, R; Mendonça, B; Crespo, E G; Ferrand, N
2006-06-01
The study of nuclear genealogies in natural populations of nonmodel organisms is expected to provide novel insights into the evolutionary history of populations, especially when developed in the framework of well-established mtDNA phylogeographical scenarios. In the Iberian Peninsula, the endemic Schreiber's green lizard Lacerta schreiberi exhibits two highly divergent and allopatric mtDNA lineages that started to split during the late Pliocene. In this work, we performed a fine-scale analysis of the putative mtDNA contact zone together with a global analysis of the patterns of variation observed at the nuclear beta-fibrinogen intron 7 (beta-fibint7). Using a combination of DNA sequencing with single-strand conformational polymorphism (SSCP) analysis, we show that the observed genealogy at the beta-fibint7 locus reveals extensive admixture between two formerly isolated lizard populations while the two mtDNA lineages remain essentially allopatric. In addition, a private beta-fibint7 haplotype detected in the single population where both mtDNA lineages were found in sympatry is probably the result of intragenic recombination between the two more common and divergent beta-fibint7 haplotypes. Our results suggest that the progressive incorporation of nuclear genealogies in investigating the ancient demography and admixture dynamics of divergent genomes will be necessary to obtain a more comprehensive picture of the evolutionary history of organisms.
Role of cyclophilins in somatolactogenic action.
Rycyzyn, M A; Clevenger, C V
2000-01-01
Prolactin (PRL) and growth hormone (GH) are members of the somatolactogenic hormone family, the pleiotropic actions of which are necessary for vertebrate growth and mammary differentiation. The basis for the specific function of these hormones has remained uncertain; however, their action is associated with internalization and translocation into the nucleus. A yeast two-hybrid screen identified an interaction between PRL and cyclophilin B (CypB), a peptidyl prolyl isomerase (PPI) found in the endoplasmic reticulum (ER), extracellular space, and nucleus. The interaction between CypB and PRL/GH was confirmed in vitro and in vivo through the use of recombinant proteins and coimmunoprecipitation studies. The exogenous addition of CypB potentiated the proliferation of PRL- and GH-dependent cell lines 18- and 40-fold, respectively. The potentiation of PRL action by CypB was accompanied by a dramatic increase in the nuclear retrotranslocation of PRL. Immunogold electron microscopy has revealed this retrotransport to occur via a vesicular pathway. A CypB mutant, termed CypB-NT, was generated that lacked the putative wild-type N-terminal nuclear localization sequence. Although CypB-NT demonstrated levels of PRL binding and PPI activity equivalent to wild-type CypB, it was incapable of mediating the nuclear retrotranslocation of PRL or enhancing PRL-driven proliferation. These studies reveal CypB as an important chaperone facilitating the nuclear retrotransport and action of the somatolactogenic hormone family.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Myre, Michael A.; O'Day, Danton H.
2005-06-24
Nucleomorphin is a novel nuclear calmodulin (CaM)-binding protein (CaMBP) containing an extensive DEED (glu/asp repeat) domain that regulates nuclear number. GFP-constructs of the 38 kDa NumA1 isoform localize as intranuclear patches adjacent to the inner nuclear membrane. The translocation of CaMBPs into nuclei has previously been shown by others to be mediated by both classic nuclear localization sequences (NLSs) and CaM-binding domains (CaMBDs). Here we show that NumA1 possesses a CaMBD ({sup 171}EDVSRFIKGKLLQKQQKIYKDLERF{sup 195}) containing both calcium-dependent-binding motifs and an IQ-like motif for calcium-independent binding. GFP-constructs containing only NumA1 residues 1-129, lacking the DEED and CaMBDs, still localized as patchesmore » at the internal periphery of nuclei thus ruling out a direct role for the CaMBD in nuclear import. These constructs contained the amino acid residues {sup 48}KKSYQDPEIIAHSRPRK{sup 64} that include both a putative bipartite and classical NLS. GFP-bipartite NLS constructs localized uniformly within nuclei but not as patches. As with previous work, removal of the DEED domain resulted in highly multinucleate cells. However as shown here, multinuclearity only occurred when the NLS was present allowing the protein to enter nuclei. Site-directed mutation analysis in which the NLS was changed to {sup 48}EF{sup 49} abolished the stability of the GFP fusion at the protein but not RNA level preventing subcellular analyses. Cells transfected with the {sup 48}EF{sup 49} construct exhibited slowed growth when compared to parental AX3 cells and other GFP-NumA1 deletion mutants. In addition to identifying an NLS that is sufficient for nuclear translocation of nucleomorphin and ruling out CaM-binding in this event, this work shows that the nuclear localization of NumA1 is crucial to its ability to regulate nuclear number in Dictyostelium.« less
Equation of state of asymmetric nuclear matter using re-projected nucleon–nucleon potentials
NASA Astrophysics Data System (ADS)
Asadi Aghbolaghi, Z.; Bigdeli, M.
2018-06-01
In this paper, we have calculated the equation of state of asymmetric nuclear matter using the lowest order constrained variational approach and Argonne family potentials with and without three-nucleon interaction (TNI) contribution. In particular, we have used the AV18 potential and the re-projected potentials, AV8‧, and AV6‧. We have also calculated the saturation properties of symmetric nuclear matter, and the nuclear symmetry energy using AV18+TNI, AV8‧+TNI and AV6‧+TNI potentials. The inclusion of TNI has modified the agreement with experiment. We have also made a comparison between our results and those of other many-body calculations.
Wei, C H; Chou, W Y; Huang, S M; Lin, C C; Chang, G G
1994-06-28
Pigeon liver malic enzyme was rapidly inactivated by micromolar concentrations of ferrous sulfate in the presence of ascorbate at neutral pH and 0 or 25 degrees C. Omitting the ascorbate or replacing the ferrous ion with manganese ion did not lead to any inactivation. Manganese, magnesium, zinc, cobalt, or calcium ion at 200 molar excess over ferrous ion offered complete protection of the enzyme from Fe(2+)-induced inactivation. Ni2+ provided partial protection, while Ba2+ or imidazole was ineffective in protection. Addition of 4 mM Mn2+ or 5 mM EDTA into a partially modified enzyme stopped further inactivation of the enzyme. Inclusion of substrates (L-malate or NADP+, singly or in combination) in the incubation mixture did not affect the inactivation rate. The enzyme inactivation was demonstrated to be followed by protein cleavage. Native pigeon liver malic enzyme had a subunit M(r) of 65,000. The inactivated enzyme with residual activity of only 0.3% was cleaved into two fragments with M(r) of 31,000 and 34,000, respectively. The cleavage site was identified as the peptide bond between Asp258 and Ile259. Native pigeon liver malic enzyme was blocked at the N-terminus. Cleavage at the putative metal-binding site exposed a new N-terminus, which was identified to be at the 34-kDa fragment containing the C-terminal half of original sequence 259-557. Our results indicated that Fe2+ catalyzed a specific oxidation of pigeon liver malic enzyme at Asp258 and/or some other essential amino acid residues that caused enzyme inactivation. The modified enzyme was then affinity cleaved at the Mn(2+)-binding site.
Characterization of uncultivable bat influenza virus using a replicative synthetic virus.
Zhou, Bin; Ma, Jingjiao; Liu, Qinfang; Bawa, Bhupinder; Wang, Wei; Shabman, Reed S; Duff, Michael; Lee, Jinhwa; Lang, Yuekun; Cao, Nan; Nagy, Abdou; Lin, Xudong; Stockwell, Timothy B; Richt, Juergen A; Wentworth, David E; Ma, Wenjun
2014-10-01
Bats harbor many viruses, which are periodically transmitted to humans resulting in outbreaks of disease (e.g., Ebola, SARS-CoV). Recently, influenza virus-like sequences were identified in bats; however, the viruses could not be cultured. This discovery aroused great interest in understanding the evolutionary history and pandemic potential of bat-influenza. Using synthetic genomics, we were unable to rescue the wild type bat virus, but could rescue a modified bat-influenza virus that had the HA and NA coding regions replaced with those of A/PR/8/1934 (H1N1). This modified bat-influenza virus replicated efficiently in vitro and in mice, resulting in severe disease. Additional studies using a bat-influenza virus that had the HA and NA of A/swine/Texas/4199-2/1998 (H3N2) showed that the PR8 HA and NA contributed to the pathogenicity in mice. Unlike other influenza viruses, engineering truncations hypothesized to reduce interferon antagonism into the NS1 protein didn't attenuate bat-influenza. In contrast, substitution of a putative virulence mutation from the bat-influenza PB2 significantly attenuated the virus in mice and introduction of a putative virulence mutation increased its pathogenicity. Mini-genome replication studies and virus reassortment experiments demonstrated that bat-influenza has very limited genetic and protein compatibility with Type A or Type B influenza viruses, yet it readily reassorts with another divergent bat-influenza virus, suggesting that the bat-influenza lineage may represent a new Genus/Species within the Orthomyxoviridae family. Collectively, our data indicate that the bat-influenza viruses recently identified are authentic viruses that pose little, if any, pandemic threat to humans; however, they provide new insights into the evolution and basic biology of influenza viruses.
Characterization of Uncultivable Bat Influenza Virus Using a Replicative Synthetic Virus
Bawa, Bhupinder; Wang, Wei; Shabman, Reed S.; Duff, Michael; Lee, Jinhwa; Lang, Yuekun; Cao, Nan; Nagy, Abdou; Lin, Xudong; Stockwell, Timothy B.; Richt, Juergen A.; Wentworth, David E.; Ma, Wenjun
2014-01-01
Bats harbor many viruses, which are periodically transmitted to humans resulting in outbreaks of disease (e.g., Ebola, SARS-CoV). Recently, influenza virus-like sequences were identified in bats; however, the viruses could not be cultured. This discovery aroused great interest in understanding the evolutionary history and pandemic potential of bat-influenza. Using synthetic genomics, we were unable to rescue the wild type bat virus, but could rescue a modified bat-influenza virus that had the HA and NA coding regions replaced with those of A/PR/8/1934 (H1N1). This modified bat-influenza virus replicated efficiently in vitro and in mice, resulting in severe disease. Additional studies using a bat-influenza virus that had the HA and NA of A/swine/Texas/4199-2/1998 (H3N2) showed that the PR8 HA and NA contributed to the pathogenicity in mice. Unlike other influenza viruses, engineering truncations hypothesized to reduce interferon antagonism into the NS1 protein didn't attenuate bat-influenza. In contrast, substitution of a putative virulence mutation from the bat-influenza PB2 significantly attenuated the virus in mice and introduction of a putative virulence mutation increased its pathogenicity. Mini-genome replication studies and virus reassortment experiments demonstrated that bat-influenza has very limited genetic and protein compatibility with Type A or Type B influenza viruses, yet it readily reassorts with another divergent bat-influenza virus, suggesting that the bat-influenza lineage may represent a new Genus/Species within the Orthomyxoviridae family. Collectively, our data indicate that the bat-influenza viruses recently identified are authentic viruses that pose little, if any, pandemic threat to humans; however, they provide new insights into the evolution and basic biology of influenza viruses. PMID:25275541
Shivakumara, Tagginahalli N; Chaudhary, Sonam; Kamaraju, Divya; Dutta, Tushar K; Papolu, Pradeep K; Banakar, Prakash; Sreevathsa, Rohini; Singh, Bhupinder; Manjaiah, K M; Rao, Uma
2017-01-01
The complex parasitic strategy of Meloidogyne incognita appears to involve simultaneous expression of its pharyngeal gland-specific effector genes in order to colonize the host plants. Research reports related to effector crosstalk in phytonematodes for successful parasitism of the host tissue is yet underexplored. In view of this, we have used in planta effector screening approach to understand the possible interaction of pioneer genes ( msp-18 and msp-20 , putatively involved in late and early stage of M. incognita parasitism, respectively) with other unrelated effectors such as cell-wall modifying enzymes (CWMEs) in M. incognita . Host-induced gene silencing (HIGS) strategy was used to generate the transgenic eggplants expressing msp-18 and msp-20 , independently. Putative transformants were characterized via qRT-PCR and Southern hybridization assay. SiRNAs specific to msp-18 and msp - 20 were also detected in the transformants via Northern hybridization assay. Transgenic expression of the RNAi constructs of msp-18 and msp-20 genes resulted in 43.64-69.68% and 41.74-67.30% reduction in M. incognita multiplication encompassing 6 and 10 events, respectively. Additionally, transcriptional oscillation of CWMEs documented in the penetrating and developing nematodes suggested the possible interaction among CWMEs and pioneer genes. The rapid assimilation of plant-derived carbon by invading nematodes was also demonstrated using 14 C isotope probing approach. Our data suggests that HIGS of msp-18 and msp-20 , improves nematode resistance in eggplant by affecting the steady-state transcription level of CWME genes in invading nematodes, and safeguard the plant against nematode invasion at very early stage because nematodes may become the recipient of bioactive RNA species during the process of penetration into the plant root.
Ying, Shibo; Dünnebier, Thomas; Si, Jing; Hamann, Ute
2013-01-01
UBC9 encodes a protein that conjugates small ubiquitin-related modifier (SUMO) to target proteins thereby changing their functions. Recently, it was noted that UBC9 expression and activity play a role in breast tumorigenesis and response to anticancer drugs. However, the underlying mechanism is poorly understood. To investigate the transcriptional regulation of the UBC9 gene, we identified and characterized its promoter and cis-elements. Promoter activity was tested using luciferase reporter assays. The binding of transcription factors to the promoter was detected by chromatin immunoprecipitation (ChIP), and their functional role was confirmed by siRNA knockdown. UBC9 mRNA and protein levels were measured by quantitative reverse transcription PCR and Western blot analysis, respectively. An increased expression of UBC9 mRNA and protein was found in MCF-7 breast cancer cells treated with 17β-estradiol (E2). Analysis of various deletion mutants revealed a 137 bp fragment upstream of the transcription initiation site to be sufficient for reporter gene transcription. Mutations of putative estrogen receptor α (ER-α) (one imperfect estrogen response element, ERE) and/or nuclear factor Y (NF-Y) binding sites (two CCAAT boxes) markedly reduced promoter activity. Similar results were obtained in ER-negative MDA-MB-231 cells except that the ERE mutation did not affect promoter activity. Additionally, promoter activity was stimulated upon E2 treatment and overexpression of ER-α or NF-YA in MCF-7 cells. ChIP confirmed direct binding of both transcription factors to the UBC9 promoter in vivo. Furthermore, UBC9 expression was diminished by ER-α and NF-Y siRNAs on the mRNA and protein levels. In conclusion, we identified the proximal UBC9 promoter and provided evidence that ER-α and NF-Y regulate UBC9 expression on the transcriptional level in response to E2 in MCF-7 cells. These findings may contribute to a better understanding of the regulation of UBC9 in ER-positive breast cancer and be useful for the development of cancer therapies targeting UBC9.
Manen, Jean-François
2004-01-01
Background Intra-specific and intra-individual polymorphism is frequently observed in nuclear markers of Ilex (Aquifoliaceae) and discrepancy between plastid and nuclear phylogenies is the rule in this genus. These observations suggest that inter-specific plastid or/and nuclear introgression played an important role in the process of evolution of Ilex. With the aim of a precise understanding of the evolution of this genus, two distantly related sympatric species collected in Tenerife (Canary Islands), I. perado and I. canariensis, were studied in detail. Introgression between these two species was previously never reported. One plastid marker (the atpB-rbcL spacer) and two nuclear markers, the ribosomal internal transcribed spacer (ITS) and the nuclear encoded plastid glutamine synthetase (nepGS) were analyzed for 13 and 27 individuals of I. perado and I. canariensis, respectively. Results The plastid marker is intra-specifically constant and correlated with species identity. On the other hand, whereas the nuclear markers are conserved in I. perado, they are highly polymorphic in I. canariensis. The presence of pseudogenes and recombination in ITS sequences of I. canariensis explain this polymorphism. Ancestral sequence polymorphism with incomplete lineage sorting, or past or recent hybridization with an unknown species could explain this polymorphism, not resolved by concerted evolution. However, as already reported for many other plants, past or recent introgression of an alien genotype seem the most probable explanation for such a tremendous polymorphism. Conclusions Data do not allow the determination with certitude of the putative species introgressing I. canariensis, but I. perado is suspected. The introgression would be unilateral, with I. perado as the male donor, and the paternal sequences would be rapidly converted in highly divergent and consequently unidentifiable pseudogenes. At least, this study allows the establishment of precautionary measures when nuclear markers are used in phylogenetic studies of genera having experienced introgression such as the genus Ilex. PMID:15550175
Pintchovski, Sean A.; Peebles, Carol L.; Kim, Hong Joo; Verdin, Eric; Finkbeiner, Steven
2010-01-01
The immediate-early effector gene Arc/Arg3.1 is robustly upregulated by synaptic activity associated with learning and memory. Here we show in primary cortical neuron culture that diverse stimuli induce Arc expression through new transcription. Searching for regulatory regions important for Arc transcription, we found nine DNaseI-sensitive nucleosome-depleted sites at this genomic locus. A reporter gene encompassing these sites responded to synaptic activity in an NMDA receptor–dependent manner, consistent with endogenous Arc mRNA. Responsiveness mapped to two enhancer regions ∼6.5 kb and ∼1.4 kb upstream of Arc. We dissected these regions further and found that the proximal enhancer contains a functional and conserved “Zeste-like” response element that binds a putative novel nuclear protein in neurons. Therefore, activity regulates Arc transcription partly by a novel signaling pathway. We also found that the distal enhancer has a functional and highly conserved serum response element. This element binds serum response factor, which is recruited by synaptic activity to regulate Arc. Thus, Arc is the first target of serum response factor that functions at synapses to mediate plasticity. PMID:19193899
Biolistic transformation of Scoparia dulcis L.
Srinivas, Kota; Muralikrishna, Narra; Kumar, Kalva Bharath; Raghu, Ellendula; Mahender, Aileni; Kiranmayee, Kasula; Yashodahara, Velivela; Sadanandam, Abbagani
2016-01-01
Here, we report for the first time, the optimized conditions for microprojectile bombardment-mediated genetic transformation in Vassourinha (Scoparia dulcis L.), a Plantaginaceae medicinal plant species. Transformation was achieved by bombardment of axenic leaf segments with Binary vector pBI121 harbouring β-glucuronidase gene (GUS) as a reporter and neomycin phosphotransferase II gene (npt II) as a selectable marker. The influence of physical parameters viz., acceleration pressure, flight distance, gap width & macroprojectile travel distance of particle gun on frequency of transient GUS and stable (survival of putative transformants) expressions have been investigated. Biolistic delivery of the pBI121 yielded the best (80.0 %) transient expression of GUS gene bombarded at a flight distance of 6 cm and rupture disc pressure/acceleration pressure of 650 psi. Highest stable expression of 52.0 % was noticed in putative transformants on RMBI-K medium. Integration of GUS and npt II genes in the nuclear genome was confirmed through primer specific PCR. DNA blot analysis showed more than one transgene copy in the transformed plantlet genomes. The present study may be used for metabolic engineering and production of biopharmaceuticals by transplastomic technology in this valuable medicinal plant.
Giger, Julia M; Haddad, Fadia; Qin, Anqi X; Baldwin, Kenneth M
2002-03-01
Functional overload (OL) of the rat plantaris muscle by the removal of synergistic muscles induces a shift in the myosin heavy chain (MHC) isoform expression profile from the fast isoforms toward the slow type I, or, beta-MHC isoform. Different length rat beta-MHC promoters were linked to a firefly luciferase reporter gene and injected in control and OL plantaris muscles. Reporter activities of -3,500, -914, -408, and -215 bp promoters increased in response to 1 wk of OL. The smallest -171 bp promoter was not responsive to OL. Mutation analyses of putative regulatory elements within the -171 and -408 bp region were performed. The -408 bp promoters containing mutations of the betae1, distal muscle CAT (MCAT; betae2), CACC, or A/T-rich (GATA), were still responsive to OL. Only the proximal MCAT (betae3) mutation abolished the OL response. Gel mobility shift assays revealed a significantly higher level of complex formation of the betae3 probe with nuclear protein from OL plantaris compared with control plantaris. These results suggest that the betae3 site functions as a putative OL-responsive element in the rat beta-MHC gene promoter.
McDowell, T L; Gibbons, R J; Sutherland, H; O'Rourke, D M; Bickmore, W A; Pombo, A; Turley, H; Gatter, K; Picketts, D J; Buckle, V J; Chapman, L; Rhodes, D; Higgs, D R
1999-11-23
ATRX is a member of the SNF2 family of helicase/ATPases that is thought to regulate gene expression via an effect on chromatin structure and/or function. Mutations in the hATRX gene cause severe syndromal mental retardation associated with alpha-thalassemia. Using indirect immunofluorescence and confocal microscopy we have shown that ATRX protein is associated with pericentromeric heterochromatin during interphase and mitosis. By coimmunofluorescence, ATRX localizes with a mouse homologue of the Drosophila heterochromatic protein HP1 in vivo, consistent with a previous two-hybrid screen identifying this interaction. From the analysis of a trap assay for nuclear proteins, we have shown that the localization of ATRX to heterochromatin is encoded by its N-terminal region, which contains a conserved plant homeodomain-like finger and a coiled-coil domain. In addition to its association with heterochromatin, at metaphase ATRX clearly binds to the short arms of human acrocentric chromosomes, where the arrays of ribosomal DNA are located. The unexpected association of a putative transcriptional regulator with highly repetitive DNA provides a potential explanation for the variability in phenotype of patients with identical mutations in the ATRX gene.
Stell, W K; Walker, S E; Chohan, K S; Ball, A K
1984-01-01
Antisera to two putative neurotransmitters, luteinizing hormone-releasing hormone (LHRH) and molluscan cardioexcitatory tetrapeptide (H-Phe-Met-Arg-Phe-NH2; FMRF-amide), bind specifically to neurites in the inner nuclear and inner plexiform layers of the goldfish retina. Retrograde labeling showed that intraocular axon terminals originate from the nervus terminalis, whose cell bodies are located in the olfactory nerves. Double immunocytochemical and retrograde labeling showed that some terminalis neurons project to the retina; others may project only within the brain. All terminalis neurons having proven retinal projections were both LHRH- and FMRF-amide-immunoreactive. The activity of retinal ganglion cells was recorded with microelectrodes in isolated superfused goldfish retinas. In ON- and OFF-center double-color-opponent cells, micromolar FMRF-amide and salmon brain gonadotropin-releasing factor ( [Trp7, Leu8] LHRH) caused increased spontaneous activity in the dark, loss of light-induced inhibition, and increased incidence of light-entrained pulsatile response. The nervus terminalis is therefore a putatively peptidergic retinopetal projection. Sex-related olfactory stimuli may act through it, thereby modulating the output of ganglion cells responsive to color contrast. Images PMID:6199789
The protein network surrounding the human telomere repeat binding factors TRF1, TRF2, and POT1
DOE Office of Scientific and Technical Information (OSTI.GOV)
Giannone, Richard J; McDonald, W Hayes; Hurst, Gregory
Telomere integrity (including telomere length and capping) is critical in overall genomic stability. Telomere repeat binding factors and their associated proteins play vital roles in telomere length regulation and end protection. In this study, we explore the protein network surrounding telomere repeat binding factors, TRF1, TRF2, and POT1 using dual-tag affinity purification in combination with multidimensional protein identification technology liquid chromatography - tandem mass spectrometry (MudPIT LC-MS/MS). After control subtraction and data filtering, we found that TRF2 and POT1 co-purified all six members of the telomere protein complex, while TRF1 identified five of six components at frequencies that lend evidencemore » towards the currently accepted telomere architecture. Many of the known TRF1 or TRF2 interacting proteins were also identified. Moreover, putative associating partners identified for each of the three core components fell into functional categories such as DNA damage repair, ubiquitination, chromosome cohesion, chromatin modification/remodeling, DNA replication, cell cycle and transcription regulation, nucleotide metabolism, RNA processing, and nuclear transport. These putative protein-protein associations may participate in different biological processes at telomeres or, intriguingly, outside telomeres.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sun, Zhen; Department of Biochemistry and Molecular Biology, Program in Molecular Cell Biology, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058; Xiang, Wenqing
Highlights: {yields} LNA-modified oligonucleotides can pass through the plasma membrane of cultured cells even without using transfection machinery. {yields} LNA-modified oligonucleotides passed efficiently across the cell membrane, and lipid-coating facilitated translocation from the cytoplasm to the nucleus. {yields} LNA-oligonucleotide designed to target nuclear HBV DNA efficiently suppresses HBV replication and transcription in cultured hepatic cells. -- Abstract: Silencing target genes with small regulatory RNAs is widely used to investigate gene function and therapeutic drug development. Recently, triplex-based approaches have provided another attractive means to achieve targeted gene regulation and gene manipulation at the molecular and cellular levels. Nuclear entry ofmore » oligonucleotides and enhancement of their affinity to the DNA targets are key points of such approaches. In this study, we developed lipid-based transport of a locked-nucleic-acid (LNA)-modified oligonucleotide for hepatitis B virus (HBV) DNA interference in human hepatocytes expressing HBV genomic DNA. In these cells, the LNA-modified oligonucleotides passed efficiently across the cell membrane, and lipid-coating facilitated translocation from the cytoplasm to the nucleus. The oligonucleotide specifically targeting HBV DNA clearly interfered with HBV DNA transcription as shown by a block in pregenomic RNA (pgRNA) production. The HBV DNA-targeted oligonucleotide suppressed HBV DNA replication and HBV protein production more efficiently than small interfering RNAs directed to the pgRNA. These results demonstrate that fusion with lipid can carry LNA-modified oligonucleotides to the nucleus where they regulate gene expression. Interfering with HBV DNA transcription by LNA-modified oligonucleotides has strong potential as a new strategy for HBV inhibition.« less
Segatto, Ana Lúcia Anversa; Thompson, Claudia Elizabeth; Freitas, Loreta Brandão
2016-01-01
Abstract Developmental genes are believed to contribute to major changes during plant evolution, from infrageneric to higher levels. Due to their putative high sequence conservation, developmental genes are rarely used as molecular markers, and few studies including these sequences at low taxonomic levels exist. WUSCHEL-related homeobox genes (WOX) are transcription factors exclusively present in plants and are involved in developmental processes. In this study, we characterized the infrageneric genetic variation of Petunia WOX genes. We obtained phylogenetic relationships consistent with other phylogenies based on nuclear markers, but with higher statistical support, resolution in terminals, and compatibility with flower morphological changes. PMID:27768156
Nuclear transport of the Neurospora crassa NIT-2 transcription factor is mediated by importin-α.
Bernardes, Natália E; Takeda, Agnes A S; Dreyer, Thiago R; Cupertino, Fernanda B; Virgilio, Stela; Pante, Nelly; Bertolini, Maria Célia; Fontes, Marcos R M
2017-12-06
The Neurospora crassa NIT-2 transcription factor belongs to the GATA transcription factor family and plays a fundamental role in the regulation of nitrogen metabolism. Because NIT-2 acts by accessing DNA inside the nucleus, understanding the nuclear import process of NIT-2 is necessary to characterize its function. Thus, in the present study, NIT-2 nuclear transport was investigated using a combination of biochemical, cellular, and biophysical methods. A complemented strain that produced an sfGFP-NIT-2 fusion protein was constructed, and nuclear localization assessments were made under conditions that favored protein translocation to the nucleus. Nuclear translocation was also investigated using HeLa cells, which showed that the putative NIT-2 nuclear localization sequence (NLS; 915 TISSKRQRRHSKS 927 ) was recognized by importin-α and that subsequent transport occurred via the classical import pathway. The interaction between the N. crassa importin-α (NcImpα) and the NIT-2 NLS was quantified with calorimetric assays, leading to the observation that the peptide bound to two sites with different affinities, which is typical of a monopartite NLS sequence. The crystal structure of the NcImpα/NIT-2 NLS complex was solved and revealed that the NIT-2 peptide binds to NcImpα with the major NLS-binding site playing a primary role. This result contrasts other recent studies that suggested a major role for the minor NLS-binding site in importin-α from the α2 family, indicating that both sites can be used for different cargo proteins according to specific metabolic requirements. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.
Corral-Ramos, Cristina; Roca, M Gabriela; Di Pietro, Antonio; Roncero, M Isabel G; Ruiz-Roldán, Carmen
2015-01-01
In the fungal pathogen Fusarium oxysporum, vegetative hyphal fusion triggers nuclear mitotic division in the invading hypha followed by migration of a nucleus into the receptor hypha and degradation of the resident nucleus. Here we examined the role of autophagy in fusion-induced nuclear degradation. A search of the F. oxysporum genome database for autophagy pathway components identified putative orthologs of 16 core autophagy-related (ATG) genes in yeast, including the ubiquitin-like protein Atg8, which is required for the formation of autophagosomal membranes. F. oxysporum Foatg8Δ mutants were generated in a strain harboring H1-cherry fluorescent protein (ChFP)-labeled nuclei to facilitate analysis of nuclear dynamics. The Foatg8Δ mutants did not show MDC-positive staining in contrast to the wild type and the FoATG8-complemented (cFoATG8) strain, suggesting that FoAtg8 is required for autophagy in F. oxysporum. The Foatg8Δ strains displayed reduced rates of hyphal growth, conidiation, and fusion, and were significantly attenuated in virulence on tomato plants and in the nonvertebrate animal host Galleria mellonella. In contrast to wild-type hyphae, which are almost exclusively composed of uninucleated hyphal compartments, the hyphae of the Foatg8Δ mutants contained a significant fraction of hyphal compartments with 2 or more nuclei. The increase in the number of nuclei per hyphal compartment was particularly evident after hyphal fusion events. Time-lapse microscopy analyses revealed abnormal mitotic patterns during vegetative growth in the Foatg8Δ mutants. Our results suggest that autophagy mediates nuclear degradation after hyphal fusion and has a general function in the control of nuclear distribution in F. oxysporum.
Corral-Ramos, Cristina; Roca, M Gabriela; Di Pietro, Antonio; Roncero, M Isabel G; Ruiz-Roldán, Carmen
2015-01-01
In the fungal pathogen Fusarium oxysporum, vegetative hyphal fusion triggers nuclear mitotic division in the invading hypha followed by migration of a nucleus into the receptor hypha and degradation of the resident nucleus. Here we examined the role of autophagy in fusion-induced nuclear degradation. A search of the F. oxysporum genome database for autophagy pathway components identified putative orthologs of 16 core autophagy-related (ATG) genes in yeast, including the ubiquitin-like protein Atg8, which is required for the formation of autophagosomal membranes. F. oxysporum Foatg8Δ mutants were generated in a strain harboring H1-cherry fluorescent protein (ChFP)-labeled nuclei to facilitate analysis of nuclear dynamics. The Foatg8Δ mutants did not show MDC-positive staining in contrast to the wild type and the FoATG8-complemented (cFoATG8) strain, suggesting that FoAtg8 is required for autophagy in F. oxysporum. The Foatg8Δ strains displayed reduced rates of hyphal growth, conidiation, and fusion, and were significantly attenuated in virulence on tomato plants and in the nonvertebrate animal host Galleria mellonella. In contrast to wild-type hyphae, which are almost exclusively composed of uninucleated hyphal compartments, the hyphae of the Foatg8Δ mutants contained a significant fraction of hyphal compartments with 2 or more nuclei. The increase in the number of nuclei per hyphal compartment was particularly evident after hyphal fusion events. Time-lapse microscopy analyses revealed abnormal mitotic patterns during vegetative growth in the Foatg8Δ mutants. Our results suggest that autophagy mediates nuclear degradation after hyphal fusion and has a general function in the control of nuclear distribution in F. oxysporum. PMID:25560310
de Barros, Andrea C; Takeda, Agnes A S; Dreyer, Thiago R; Velazquez-Campoy, Adrian; Kobe, Boštjan; Fontes, Marcos R M
2018-03-01
MLH1 and PMS2 proteins form the MutLα heterodimer, which plays a major role in DNA mismatch repair (MMR) in humans. Mutations in MMR-related proteins are associated with cancer, especially with colon cancer. The N-terminal region of MutLα comprises the N-termini of PMS2 and MLH1 and, similarly, the C-terminal region of MutLα is composed by the C-termini of PMS2 and MLH1, and the two are connected by linker region. The nuclear localization sequences (NLSs) necessary for the nuclear transport of the two proteins are found in this linker region. However, the exact NLS sequences have been controversial, with different sequences reported, particularly for MLH1. The individual components are not imported efficiently, presumably due to their C-termini masking their NLSs. In order to gain insights into the nuclear transport of these proteins, we solved the crystal structures of importin-α bound to peptides corresponding to the supposed NLSs of MLH1 and PMS2 and performed isothermal titration calorimetry to study their binding affinities. Both putative MLH1 and PMS2 NLSs can bind to importin-α as monopartite NLSs, which is in agreement with some previous studies. However, MLH1-NLS has the highest affinity measured by a natural NLS peptide, suggesting a major role of MLH1 protein in nuclear import compared to PMS2. Finally, the role of MLH1 and PMS2 in the nuclear transport of the MutLα heterodimer is discussed. Copyright © 2017 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.
Texas Should Require Homeland Security Standards for High-Speed Rail
2015-12-01
conditions. Japanese trains, engineered with earthquakes in mind, all came to a safe stop during the 2011 Fukushima disaster without loss of life or...building—that devastated parts of Japan through immediate effect as well as caused the consequential breach of the Fukushima nuclear reactor.119...119 Ichiro Fujisaki, “Japan’s Recovery Six Months after the Earthquake, Tsunami and Nuclear Crisis,” Brookings Institution, last modified September
Parish, E J; Wei, T Y; Livant, P
1987-10-01
This paper presents a modified method of the selective allylic oxidation of cholesteryl benzoate. Pyridinium chlorochromate, in refluxing benzene, has been found to be an effective and convenient reagent for the efficient oxidation of cholesteryl benzoate to 7-ketocholesteryl benzoate in high yield. Also included herein are the carbon-13 nuclear magnetic resonance spectral properties of 7-ketocholesteryl benzoate and cholesteryl benzoate.
How DARHT Works - the World's Most Powerful X-ray Machine
None
2018-06-01
The Dual Axis Radiographic Hydrodynamic Test (DARHT) facility at Los Alamos National Laboratory is an essential scientific tool that supports Stockpile Stewardship at the Laboratory. The World's most powerful x-ray machine, it's used to take high-speed images of mock nuclear devices - data that is used to confirm and modify advanced computer codes in assuring the safety, security, and effectiveness of the U.S. nuclear deterrent.
Portnoy, D S; Puritz, J B; Hollenbeck, C M; Gelsleichter, J; Chapman, D; Gold, J R
2015-12-01
Sex-biased dispersal is expected to homogenize nuclear genetic variation relative to variation in genetic material inherited through the philopatric sex. When site fidelity occurs across a heterogeneous environment, local selective regimes may alter this pattern. We assessed spatial patterns of variation in nuclear-encoded, single nucleotide polymorphisms (SNPs) and sequences of the mitochondrial control region in bonnethead sharks (Sphyrna tiburo), a species thought to exhibit female philopatry, collected from summer habitats used for gestation. Geographic patterns of mtDNA haplotypes and putatively neutral SNPs confirmed female philopatry and male-mediated gene flow along the northeastern coast of the Gulf of Mexico. A total of 30 outlier SNP loci were identified; alleles at over half of these loci exhibited signatures of latitude-associated selection. Our results indicate that in species with sex-biased dispersal, philopatry can facilitate sorting of locally adaptive variation, with the dispersing sex facilitating movement of potentially adaptive variation among locations and environments. © 2015 John Wiley & Sons Ltd.
Comprehensive proteomic analysis of the human spliceosome
NASA Astrophysics Data System (ADS)
Zhou, Zhaolan; Licklider, Lawrence J.; Gygi, Steven P.; Reed, Robin
2002-09-01
The precise excision of introns from pre-messenger RNA is performed by the spliceosome, a macromolecular machine containing five small nuclear RNAs and numerous proteins. Much has been learned about the protein components of the spliceosome from analysis of individual purified small nuclear ribonucleoproteins and salt-stable spliceosome `core' particles. However, the complete set of proteins that constitutes intact functional spliceosomes has yet to be identified. Here we use maltose-binding protein affinity chromatography to isolate spliceosomes in highly purified and functional form. Using nanoscale microcapillary liquid chromatography tandem mass spectrometry, we identify ~145 distinct spliceosomal proteins, making the spliceosome the most complex cellular machine so far characterized. Our spliceosomes comprise all previously known splicing factors and 58 newly identified components. The spliceosome contains at least 30 proteins with known or putative roles in gene expression steps other than splicing. This complexity may be required not only for splicing multi-intronic metazoan pre-messenger RNAs, but also for mediating the extensive coupling between splicing and other steps in gene expression.
Histone H3 is absent from organelle nucleoids in BY-2 cultured tobacco cells.
Takusagawa, Mari; Tamotsu, Satoshi; Sakai, Atsushi
2013-07-01
The core histone proteins (H2A, H2B, H3 and H4) are nuclear-localised proteins that play a central role in the formation of nucleosome structure. They have long been considered to be absent from extra-nuclear, DNA-containing organelles; that is plastids and mitochondria. Recently, however, the targeting of core histone H3 to mitochondria, and the presence of nucleosome-like structures in mitochondrial nucleoids, were proposed in cauliflower and tobacco respectively. Thus, we examined whether histone H3 was present in plant organelles and participated in the organisation of nucleoid structure, using highly purified organelles and organelle nucleoids isolated from BY-2 cultured tobacco cells. Immunofluorescence microscopic observations and Western blotting analyses demonstrated that histone H3 was absent from organelles and organelle nucleoids, consistent with the historical hypothesis. Thus, the organisation of organelle nucleoids, including putative nucleosome-like repetitive structures, should be constructed and maintained without participation of histone H3. © 2013 International Federation for Cell Biology.
A functional network involved in the recycling of nucleocytoplasmic pre-60S factors
Lebreton, Alice; Saveanu, Cosmin; Decourty, Laurence; Rain, Jean-Christophe; Jacquier, Alain; Fromont-Racine, Micheline
2006-01-01
Eukaryotic pre-ribosomes go through cytoplasmic maturation steps before entering translation. The nucleocytoplasmic proteins participating in these late stages of maturation are reimported to the nucleus. In this study, we describe a functional network focused on Rei1/Ybr267w, a strictly cytoplasmic pre-60S factor indirectly involved in nuclear 27S pre-ribosomal RNA processing. In the absence of Rei1, the nuclear import of at least three other pre-60S factors is impaired. The accumulation in the cytoplasm of a small complex formed by the association of Arx1 with a novel factor, Alb1/Yjl122w, inhibits the release of the putative antiassociation factor Tif6 from the premature large ribosomal subunits and its recycling to the nucleus. We propose a model in which Rei1 is a key factor for the coordinated dissociation and recycling of the last pre-60S factors before newly synthesized large ribosomal subunits enter translation. PMID:16651379
Meseguer, Salvador; Martínez-Zamora, Ana; García-Arumí, Elena; Andreu, Antonio L; Armengod, M-Eugenia
2015-01-01
Mitochondrial dysfunction activates mitochondria-to-nucleus signaling pathways whose components are mostly unknown. Identification of these components is important to understand the molecular mechanisms underlying mitochondrial diseases and to discover putative therapeutic targets. MELAS syndrome is a rare neurodegenerative disease caused by mutations in mitochondrial (mt) DNA affecting mt-tRNA(Leu(UUR)). Patient and cybrid cells exhibit elevated oxidative stress. Moreover, mutant mt-tRNAs(Leu(UUR)) lack the taurine-containing modification normally present at the wobble uridine (U34) of wild-type mt-tRNA(Leu(UUR)), which is considered an etiology of MELAS. However, the molecular mechanism is still unclear. We found that MELAS cybrids exhibit a significant decrease in the steady-state levels of several mt-tRNA-modification enzymes, which is not due to transcriptional regulation. We demonstrated that oxidative stress mediates an NFkB-dependent induction of microRNA-9/9*, which acts as a post-transcriptional negative regulator of the mt-tRNA-modification enzymes GTPBP3, MTO1 and TRMU. Down-regulation of these enzymes by microRNA-9/9* affects the U34 modification status of non-mutant tRNAs and contributes to the MELAS phenotype. Anti-microRNA-9 treatments of MELAS cybrids reverse the phenotype, whereas miR-9 transfection of wild-type cells mimics the effects of siRNA-mediated down-regulation of GTPBP3, MTO1 and TRMU. Our data represent the first evidence that an mt-DNA disease can directly affect microRNA expression. Moreover, we demonstrate that the modification status of mt-tRNAs is dynamic and that cells respond to stress by modulating the expression of mt-tRNA-modifying enzymes. microRNA-9/9* is a crucial player in mitochondria-to-nucleus signaling as it regulates expression of nuclear genes in response to changes in the functional state of mitochondria. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Dai, Xiangpeng; Hao, Jie; Zhou, Qi
2009-08-01
Many strategies have been established to improve the efficiency of somatic cell nuclear transfer (SCNT), but relatively few focused on improving culture conditions. The effect of different culture media on preimplantation development of mouse nuclear transfer embryos was investigated. A modified sequential media method, named D media (M16/KSOM and CZB-EG/KSOM), was successfully established that significantly improves SCNT embryo development. Our result demonstrated that while lacking any adverse effect on in vivo fertilized embryos, the D media dramatically improves the blastocyst development of SCNT embryos compared with other commonly used media, including KSOM, M16, CZB, and alphaMEM. Specifically, the rate of blastocyst formation was 62.3% for D1 (M16/KSOM) versus 10-30% for the other media. An analysis of media components indicated that removing EDTA and glutamine from the media can be beneficial for early SCNT embryo development. Our results suggest that in vitro culture environment plays an important role in somatic cell reprogramming, and D media represent the most efficient culture method reported to date to support mouse SCNT early embryo development in vitro.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Abriola, D.; Tuli, J.
The IAEA Nuclear Data Section convened the 18th meeting of the International Network of Nuclear Structure and Decay Data Evaluators at the IAEA Headquarters, Vienna, 23 to 27 March 2009. This meeting was attended by 22 scientists from 14 Member States, plus IAEA staff, concerned with the compilation, evaluation and dissemination of nuclear structure and decay data. A summary of the meeting, recommendations/conclusions, data centre reports, and various proposals considered, modified and agreed by the participants are contained within this document. The International Network of Nuclear Structure and Decay Data (NSDD) Evaluators holds biennial meetings under the auspices of themore » IAEA, and consists of evaluation groups and data service centres in several countries. This network has the objective of providing up-to-date nuclear structure and decay data for all known nuclides by evaluating all existing experimental data. Data resulting from this international evaluation collaboration is included in the Evaluated Nuclear Structure Data File (ENSDF) and published in the journals Nuclear Physics A and Nuclear Data Sheets (NDS).« less
Chazin, W J; Rance, M; Chollet, A; Leupin, W
1991-01-01
The dodecadeoxynucleotide duplex d-(GCATTAATGC)2 has been prepared with all adenine bases replaced by 2-NH2-adenine. This modified duplex has been characterized by nuclear magnetic resonance (NMR) spectroscopy. Complete sequence-specific 1H resonance assignments have been obtained by using a variety of 2D NMR methods. Multiple quantum-filtered and multiple quantum experiments have been used to completely assign all sugar ring protons, including 5'H and 5'H resonances. The assignments form the basis for a detailed comparative analysis of the 1H NMR parameters of the modified and parent duplex. The structural features of both decamer duplexes in solution are characteristic of the B-DNA family. The spin-spin coupling constants in the sugar rings and the relative spatial proximities of protons in the bases and sugars (as determined from the comparison of corresponding nuclear Overhauser effects) are virtually identical in the parent and modified duplexes. Thus, substitution by this adenine analogue in oligonucleotides appears not to disturb the global or local conformation of the DNA duplex. PMID:1945828
Study of p-4He total reaction cross-section using Glauber and Coulomb-modified Glauber models
NASA Astrophysics Data System (ADS)
Tag El-Din, Ibrahim M. A.; Taha, M. M.; Hassan, Samia S. A.
2014-02-01
The total nuclear reaction cross-section σR for p-4He in the energy range from 25 MeV to 1000 MeV is calculated within Glauber and Coulomb-modified Glauber models. The Coulomb-modified Glauber model (CMGM) is introduced via modification of the Coulomb trajectory of the projectile from a straight line, and calculation of the effective radius of interaction. The effects of in-medium nucleon-nucleon (NN) total cross-section, phase variation, high order momentum transfer component of nucleon-nucleon elastic scattering amplitude and Pauli blocking are studied. It is pointed out that the phase variation of the nucleon-nucleon amplitude plays a significant role in describing σR with γ = -1.6 fm2 at in-medium nuclear density ϱ = 0 and γ = -2 fm2 at ϱ = 0.17 fm-3 in the whole energy range. A remarkable fit to the available experimental data is obtained by invoking Pauli blocking and high order momentum transfer of nucleon-nucleon (NN) elastic scattering amplitude for Ep < 100 MeV.
Mitochondrial-epigenetic crosstalk in environmental toxicology.
Weinhouse, Caren
2017-11-01
Crosstalk between the nuclear epigenome and mitochondria, both in normal physiological function and in responses to environmental toxicant exposures, is a developing sub-field of interest in environmental and molecular toxicology. The majority (∼99%) of mitochondrial proteins are encoded in the nuclear genome, so programmed communication among nuclear, cytoplasmic, and mitochondrial compartments is essential for maintaining cellular health. In this review, we will focus on correlative and mechanistic evidence for direct impacts of each system on the other, discuss demonstrated or potential crosstalk in the context of chemical insult, and highlight biological research questions for future study. We will first review the two main signaling systems: nuclear signaling to the mitochondria [anterograde signaling], best described in regulation of oxidative phosphorylation (OXPHOS) and mitochondrial biogenesis in response to environmental signals received by the nucleus, and mitochondrial signals to the nucleus [retrograde signaling]. Both signaling systems can communicate intracellular energy needs or a need to compensate for dysfunction to maintain homeostasis, but both can also relay inappropriate signals in the presence of dysfunction in either system and contribute to adverse health outcomes. We will first review these two signaling systems and highlight known or biologically feasible epigenetic contributions to both, then briefly discuss the emerging field of epigenetic regulation of the mitochondrial genome, and finally discuss putative "crosstalk phenotypes", including biological phenomena, such as caloric restriction, maintenance of stemness, and circadian rhythm, and states of disease or loss of function, such as cancer and aging, in which both the nuclear epigenome and mitochondria are strongly implicated. Copyright © 2017 Elsevier B.V. All rights reserved.
Positive Selection in Rapidly Evolving Plastid–Nuclear Enzyme Complexes
Rockenbach, Kate; Havird, Justin C.; Monroe, J. Grey; Triant, Deborah A.; Taylor, Douglas R.; Sloan, Daniel B.
2016-01-01
Rates of sequence evolution in plastid genomes are generally low, but numerous angiosperm lineages exhibit accelerated evolutionary rates in similar subsets of plastid genes. These genes include clpP1 and accD, which encode components of the caseinolytic protease (CLP) and acetyl-coA carboxylase (ACCase) complexes, respectively. Whether these extreme and repeated accelerations in rates of plastid genome evolution result from adaptive change in proteins (i.e., positive selection) or simply a loss of functional constraint (i.e., relaxed purifying selection) is a source of ongoing controversy. To address this, we have taken advantage of the multiple independent accelerations that have occurred within the genus Silene (Caryophyllaceae) by examining phylogenetic and population genetic variation in the nuclear genes that encode subunits of the CLP and ACCase complexes. We found that, in species with accelerated plastid genome evolution, the nuclear-encoded subunits in the CLP and ACCase complexes are also evolving rapidly, especially those involved in direct physical interactions with plastid-encoded proteins. A massive excess of nonsynonymous substitutions between species relative to levels of intraspecific polymorphism indicated a history of strong positive selection (particularly in CLP genes). Interestingly, however, some species are likely undergoing loss of the native (heteromeric) plastid ACCase and putative functional replacement by a duplicated cytosolic (homomeric) ACCase. Overall, the patterns of molecular evolution in these plastid–nuclear complexes are unusual for anciently conserved enzymes. They instead resemble cases of antagonistic coevolution between pathogens and host immune genes. We discuss a possible role of plastid–nuclear conflict as a novel cause of accelerated evolution. PMID:27707788
The nuclear matrix prepared by amine modification
Wan, Katherine M.; Nickerson, Jeffrey A.; Krockmalnic, Gabriela; Penman, Sheldon
1999-01-01
The nucleus is spatially ordered by attachments to a nonchromatin nuclear structure, the nuclear matrix. The nuclear matrix and chromatin are intimately connected and integrated structures, and so a major technical challenge in nuclear matrix research has been to remove chromatin while retaining a native nuclear matrix. Most methods for removing chromatin require first a nuclease digestion and then a salt extraction to remove cut chromatin. We have hypothesized that cut chromatin is held in place by charge interactions involving nucleosomal amino groups. We have tested this hypothesis by chemically modifying amino groups after nuclease digestion. By using this protocol, chromatin could be effectively removed at physiological ionic strength. We compared the ultrastructure and composition of this nuclear matrix preparation with the traditional high-salt nuclear matrix and with the third nuclear matrix preparation that we have developed from which chromatin is removed after extensive crosslinking. All three matrix preparations reveal internal nuclear matrix structures that are built on a network of branched filaments of about 10 nm diameter. That such different chromatin-removal protocols reveal similar principles of nuclear matrix construction increases our confidence that we are observing important architectural elements of the native structure in the living cell. PMID:9927671
Monoamine oxidase-B inhibition in the treatment of Parkinson's disease.
Fernandez, Hubert H; Chen, Jack J
2007-12-01
Inhibitors of monoamine oxidase (MAO) with selectivity and specificity for MAO type B prolong the activity of both endogenously and exogenously derived dopamine, making them an option either as monotherapy in early Parkinson's disease or as adjunctive therapy in patients treated with levodopa who are experiencing motor complications. In addition to symptomatic benefits, experimental data suggest that MAO-B inhibitors may be neuroprotective through MAO-B inhibition and other mechanisms that have yet to be clearly defined. The two available MAO-B inhibitors approved for use in the United States, rasagiline and selegiline, each provide symptomatic relief as monotherapy and as adjunctive therapy, and have shown potential disease-modifying effects in experimental models and clinical studies. Selegiline in a conventional tablet formulation is less bioavailable than rasagiline, resulting in limited potency. It also has amphetamine metabolites that may produce adverse effects and interfere with any putative disease-modifying effects. The oral disintegrating tablet formulation of selegiline allows pregastric absorption, minimizing first-pass metabolism, thereby increasing selegiline bioavailability and reducing the concentration of amphetamine metabolites. Rasagiline, more potent than selegiline, exhibits disease-modifying effects in experimental models and lacks amphetamine metabolites. Both the symptomatic and potential disease-modifying effects of rasagiline are under investigation. A third agent with MAO-B inhibition properties, safinamide, is in phase III development. Although not yet approved, safinamide may offer the added advantage of combined MAO-B and dopamine reuptake inhibition.
Assessing the Effect of Musical Congruency on Wine Tasting in a Live Performance Setting
Wang, Qian (Janice)
2015-01-01
At a wine tasting event with live classical music, we assessed whether participants would agree that certain wine and music pairings were congruent. We also assessed the effect of musical congruency on the wine tasting experience. The participants were given two wines to taste and two pieces of music—one chosen to match each wine—were performed live. Half of the participants tasted the wines while listening to the putatively more congruent music, the rest tasted the wines while listening to the putatively less congruent music. The participants rated the wine–music match and assessed the fruitiness, acidity, tannins, richness, complexity, length, and pleasantness of the wines. The results revealed that the music chosen to be congruent with each wine was indeed rated as a better match than the other piece of music. Furthermore, the music playing in the background also had a significant effect on the perceived acidity and fruitiness of the wines. These findings therefore provide further support for the view that music can modify the wine drinking experience. However, the present results leave open the question of whether the crossmodal congruency between music and wine itself has any overarching influence on the wine drinking experience. PMID:27433313
Zárský, Viktor; Potocký, Martin
2010-04-01
The Rho/Rop small GTPase regulatory module is central for initiating exocytotically ACDs (active cortical domains) in plant cell cortex, and a growing array of Rop regulators and effectors are being discovered in plants. Structural membrane phospholipids are important constituents of cells as well as signals, and phospholipid-modifying enzymes are well known effectors of small GTPases. We have shown that PLDs (phospholipases D) and their product, PA (phosphatidic acid), belong to the regulators of the secretory pathway in plants. We have also shown that specific NOXs (NADPH oxidases) producing ROS (reactive oxygen species) are involved in cell growth as exemplified by pollen tubes and root hairs. Most plant cells exhibit several distinct plasma membrane domains (ACDs), established and maintained by endocytosis/exocytosis-driven membrane protein recycling. We proposed recently the concept of a 'recycling domain' (RD), uniting the ACD and the connected endosomal recycling compartment (endosome), as a dynamic spatiotemporal entity. We have described a putative GTPase-effector complex exocyst involved in exocytic vesicle tethering in plants. Owing to the multiplicity of its Exo70 subunits, this complex, along with many RabA GTPases (putative recycling endosome organizers), may belong to core regulators of RD organization in plants.
Gajski, Goran; Garaj-Vrhovac, Vera; Orescanin, Visnja
2008-08-15
To investigate the genotoxic potential of atorvastatin on human lymphocytes in vitro standard comet assay was used in the evaluation of basal DNA damage and to investigate possible oxidative DNA damage produced by reactive oxygen species (ROS) Fpg-modified version of comet assay was also conducted. In addition to these techniques the new criteria for scoring micronucleus test were applied for more complete detection of baseline damage in binuclear lymphocytes exposed to atorvastatin 80 mg/day in different time periods by virtue of measuring the frequency of micronuclei, nucleoplasmic bridges and nuclear buds. All parameters obtained with the standard comet assay and Fpg-modified comet assay were significantly higher in the treated than in control lymphocytes. The Fpg-modified comet assay showed a significantly greater tail length, tail intensity, and tail moment in all treated lymphocytes than did the standard comet assay, which suggests that oxidative stress is likely to be responsible for DNA damage. DNA damage detected by the standard comet assay indicates that some other mechanism is also involved. In addition to the comet assay, a total number of micronuclei, nucleoplasmic bridges and nuclear buds were significantly higher in the exposed than in controlled lymphocytes. Regression analyses showed a positive correlation between the results obtained by the comet (Fpg-modified and standard) and micronucleus assay. Overall, the study demonstrated that atorvastatin in its highest dose is capable of producing damage on the level of DNA molecule and cell.
Cooper, Wendy N.; Dickinson, Rachel E.; Dallol, Ashraf; Grigorieva, Elvira V.; Pavlova, Tatiana V.; Hesson, Luke B.; Bieche, Ivan; Broggini, Massimo; Maher, Eamonn R; Zabarovsky, Eugene R.; Clark, Geoffrey J; Latif, Farida
2010-01-01
RASSF2 is a recently identified member of a class of novel tumour suppressor genes, all containing a ras association domain. We previously demonstrated that the A isoform of RASSF2, is frequently inactivated by promoter region hypermethylation in colorectal tumours and adenomas, methylation was tumour specific and that expression in methylated tumour lines could be reactivated by treatment with 5-aza-2dc. RASSF2 resides at 20p13, this region has been demonstrated to be frequently lost in human cancers. In this report we investigated methylation status of the RASSF2A promoter CpG island in a series of breast, ovarian and non-small cell lung cancers (NSCLC). RASSF2A was frequently methylated in breast tumour cell lines 65% (13/20) and in primary breast tumours 38% (15/40). RASSF2A gene expression could be switched back on in methylated breast tumour cell lines after treatment with 5-aza-2dC, whilst unmethylated lines showed no difference in level of expression before and after 5-aza-2dC treatment. RASSF2A was also frequently methylated in NSCLC tumours 44% (22/50). Methylation in breast tumours and NSCLC was tumour specific. We did not detect RASSF2A methylation in ovarian tumours (0/17). Furthermore no mutations were found in the coding region of RASSF2A in these ovarian tumours. RASSF2A suppressed breast tumour cell growth in vitro (through colony formation and soft agar assays) and in vivo. We identified a highly conserved putative bipartite nuclear localisation signal (NLS) between amino acids 151 and 167 in the RASSF2A sequence and demonstrated that endogenous RASSF2A localised to the nucleus. Mutation of the putative nuclear localisation signal abolished the nuclear localisation so RASSF2A became predominantly cytoplasmic. Our data indicates that RASSF2A is frequently methylated in colorectal, breast and NSCLC tumours, furthermore, the methylation is tumour specific. Hence we have identified RASSF2A as a novel methylation marker for multiple malignancies and it has the potential to be developed into a valuable marker for screening several cancers in parallel using promoter hypermethylation profiles. We also demonstrate that RASSF2 has a functional NLS signal. Furthermore this is the first report demonstrating that RASSF2 suppresses growth of cancer cells in vivo. Hence providing further evidence for its role as a tumour suppressor gene located at 20p13. PMID:17891178
Dynamic Assembly of Brambleberry Mediates Nuclear Envelope Fusion during Early Development
Abrams, Elliott W.; Zhang, Hong; Marlow, Florence L.; Kapp, Lee; Lu, Sumei; Mullins, Mary C.
2012-01-01
Summary To accommodate the large cells following zygote formation, early blastomeres employ modified cell divisions. Karyomeres are one such modification, a mitotic intermediate wherein individual chromatin masses are surrounded by nuclear envelope, which then fuse to form a single mononucleus. We identified brambleberry, a maternal-effect zebrafish mutant that disrupts karyomere fusion resulting in formation of multiple micronuclei. brambleberry is a previously unannotated gene homologous to Kar5p, which participates in nuclear fusion in yeast. We demonstrate that Brambleberry is required for pronuclear fusion following fertilization in zebrafish. As karyomeres form, Brambleberry localizes to the nuclear envelope with prominent puncta evident near karyomere-karyomere interfaces corresponding to membrane fusion sites. Our studies identify the first factor acting in karyomere fusion and suggest that specialized proteins are necessary for proper nuclear division in large dividing blastomeres. PMID:22863006
NASA Astrophysics Data System (ADS)
Hixson, Laurie L.; Houts, Michael G.; Clement, Steven D.
2004-02-01
The extent to which, if any, full power ground nuclear testing of space reactors should be performed has been a point of discussion within the industry for decades. Do the benefits outweigh the risks? Are there equivalent alternatives? Can a test facility be constructed (or modified) in a reasonable amount of time? Is the test article an accurate representation of the flight system? Are the costs too restrictive? The obvious benefits of full power ground nuclear testing; obtaining systems integrated reliability data on a full-scale, complete end-to-end system; come at some programmatic risk. Safety related information is not obtained from a full-power ground nuclear test. This paper will discuss and assess these and other technical considerations essential in the decision to conduct full power ground nuclear-or alternative-tests.
Transmutation Fuel Performance Code Thermal Model Verification
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gregory K. Miller; Pavel G. Medvedev
2007-09-01
FRAPCON fuel performance code is being modified to be able to model performance of the nuclear fuels of interest to the Global Nuclear Energy Partnership (GNEP). The present report documents the effort for verification of the FRAPCON thermal model. It was found that, with minor modifications, FRAPCON thermal model temperature calculation agrees with that of the commercial software ABAQUS (Version 6.4-4). This report outlines the methodology of the verification, code input, and calculation results.
Power Calculations and Placebo Effect for Future Clinical Trials in Progressive Supranuclear Palsy
Stamelou, Maria; Schöpe, Jakob; Wagenpfeil, Stefan; Ser, Teodoro Del; Bang, Jee; Lobach, Iryna Y.; Luong, Phi; Respondek, Gesine; Oertel, Wolfgang H.; Boxer, Adam L.; Höglinger, Günter U.
2016-01-01
Background Two recent randomized, placebo-controlled trials of putative disease-modifying agents (davunetide, tideglusib) in progressive supranuclear palsy (PSP) failed to show efficacy, but generated data relevant for future trials. Methods We provide sample size calculations based on data collected in 187 PSP patients assigned to placebo in these trials. A placebo effect was calculated. Results The total PSP-Rating Scale required the least number of patients per group (N = 51) to detect a 50% change in the 1-year progression and 39 when including patients with ≤ 5 years disease duration. The Schwab and England Activities of Daily Living required 70 patients per group and was highly correlated with the PSP-Rating Scale. A placebo effect was not detected in these scales. Conclusions We propose the 1-year PSP-Rating Scale score change as the single primary readout in clinical neuroprotective or disease-modifying trials. The Schwab and England Activities of Daily Living could be used as a secondary outcome. PMID:26948290
Tsfasman, Tatyana; Kost, Vladimir; Markushin, Stanislav; Lotte, Vera; Koptiaeva, Irina; Bogacheva, Elena; Baratova, Ludmila; Radyukhin, Victor
2015-12-02
The influenza virus matrix M1 protein is an amphitropic membrane-associated protein, forming the matrix layer immediately beneath the virus raft membrane, thereby ensuring the proper structure of the influenza virion. The objective of this study was to elucidate M1 fine structural characteristics, which determine amphitropic properties and raft membrane activities of the protein, via 3D in silico modelling with subsequent mutational analysis. Computer simulations suggest the amphipathic nature of the M1 α-helices and the existence of putative cholesterol binding (CRAC) motifs on six amphipathic α-helices. Our finding explains for the first time many features of this protein, particularly the amphitropic properties and raft/cholesterol binding potential. To verify these results, we generated mutants of the A/WSN/33 strain via reverse genetics. The M1 mutations included F32Y in the CRAC of α-helix 2, W45Y and W45F in the CRAC of α-helix 3, Y100S in the CRAC of α-helix 6, M128A and M128S in the CRAC of α-helix 8 and a double L103I/L130I mutation in both a putative cholesterol consensus motif and the nuclear localisation signal. All mutations resulted in viruses with unusual filamentous morphology. Previous experimental data regarding the morphology of M1-gene mutant influenza viruses can now be explained in structural terms and are consistent with the pivotal role of the CRAC-domains and amphipathic α-helices in M1-lipid interactions. Copyright © 2015 Elsevier B.V. All rights reserved.
Electron microscopy of lamin and the nuclear lamina in Caenorhabditis elegans.
Cohen, Merav; Santarella, Rachel; Wiesel, Naama; Mattaj, Iain; Gruenbaum, Yosef
2008-01-01
The nuclear lamina is found between the inner nuclear membrane and the peripheral chromatin. Lamins are the main components of the nuclear lamina, where they form protein complexes with integral proteins of the inner nuclear membrane, transcriptional regulators, histones and chromatin modifiers. Lamins are required for mechanical stability, chromatin organization, Pol II transcription, DNA replication, nuclear assembly, and nuclear positioning. Mutations in human lamins cause at least 13 distinct human diseases, collectively termed laminopathies, affecting muscle, adipose, bone, nerve and skin cells, and range from muscular dystrophies to accelerated aging. Caenorhabditis elegans has unique advantages in studying lamins and nuclear lamina genes including low complexity of lamina genes and the unique ability of bacterially expressed C. elegans lamin protein to form stable 10 nm fibers. In addition, transgenic techniques, simple application of RNA interference, sophisticated genetic analyses, and the production of a large collection of mutant lines, all make C. elegans especially attractive for studying the functions of its nuclear lamina genes. In this chapter we will include a short review of our current knowledge of nuclear lamina in C. elegans and will describe electron microscopy techniques used for their analyses.
Chun, Younghwa; Park, Byoungwoo; Koh, Wansoo; Lee, Sunhee; Cheon, Yeongmi; Kim, Raehyung; Che, Lihua; Lee, Soojin
2011-01-01
CENP-W was originally identified as a putative oncogene, cancer-upregulated gene 2 (CUG2) that was commonly up-regulated in many cancer tissues. Recently, CENP-W has also been identified as a new centromeric component that interacts with CENP-T. As a complex with CENP-T, CENP-W plays crucial roles in assembly of the functional kinetochore complex. In this study, the subnuclear localization of CENP-W was extensively analyzed using various approaches. We found that ectopically expressed CENP-W primarily accumulated in the nucleolus and remained substantially associated with the nucleolus in stable cells. The following fractionation study also showed that CENP-W is associated with RNA as well as DNA. Moreover, a considerable amount of CENP-W was found in the nuclear mesh-like structure, nuclear matrix, possibly indicating that CENP-W participates in diverse subnuclear activities. Finally, biochemical affinity binding analysis revealed that CENP-W specifically interacts with the nucleolar phosphoprotein, nucleophosmin (B23). Depletion of cellular B23 by siRNA treatment induced a dramatic decrease of CENP-W stability and severe mislocalization during prophase. Our data proposed that B23 may function in the assembly of the kinetochore complex by interacting with CENP-W during interphase. PMID:22002061
Zhang, Lei; Davies, Laura J; Elling, Axel A
2015-01-01
Root-knot nematodes are sedentary biotrophic endoparasites that maintain a complex interaction with their host plants. Nematode effector proteins are synthesized in the oesophageal glands of nematodes and secreted into plant tissue through a needle-like stylet. Effectors characterized to date have been shown to mediate processes essential for nematode pathogenesis. To gain an insight into their site of action and putative function, the subcellular localization of 13 previously isolated Meloidogyne incognita effectors was determined. Translational fusions were created between effectors and EGFP-GUS (enhanced green fluorescent protein-β-glucuronidase) reporter genes, which were transiently expressed in tobacco leaf cells. The majority of effectors localized to the cytoplasm, with one effector, 7H08, imported into the nuclei of plant cells. Deletion analysis revealed that the nuclear localization of 7H08 was mediated by two novel independent nuclear localization domains. As a result of the nuclear localization of the effector, 7H08 was tested for the ability to activate gene transcription. 7H08 was found to activate the expression of reporter genes in both yeast and plant systems. This is the first report of a plant-parasitic nematode effector with transcriptional activation activity. © 2014 BSPP AND JOHN WILEY & SONS LTD.
Ranade, Sonali Sachin; García-Gil, María Rosario; Rosselló, Josep A
2016-04-01
Many genes have been lost from the prokaryote plastidial genome during the early events of endosymbiosis in eukaryotes. Some of them were definitively lost, but others were relocated and functionally integrated to the host nuclear genomes through serial events of gene transfer during plant evolution. In gymnosperms, plastid genome sequencing has revealed the loss of ndh genes from several species of Gnetales and Pinaceae, including Norway spruce (Picea abies). This study aims to trace the ndh genes in the nuclear and organellar Norway spruce genomes. The plastid genomes of higher plants contain 11 ndh genes which are homologues of mitochondrial genes encoding subunits of the proton-pumping NADH-dehydrogenase (nicotinamide adenine dinucleotide dehydrogenase) or complex I (electron transport chain). Ndh genes encode 11 NDH polypeptides forming the Ndh complex (analogous to complex I) which seems to be primarily involved in chloro-respiration processes. We considered ndh genes from the plastidial genome of four gymnosperms (Cryptomeria japonica, Cycas revoluta, Ginkgo biloba, Podocarpus totara) and a single angiosperm species (Arabidopsis thaliana) to trace putative homologs in the nuclear and organellar Norway spruce genomes using tBLASTn to assess the evolutionary fate of ndh genes in Norway spruce and to address their genomic location(s), structure, integrity and functionality. The results obtained from tBLASTn were subsequently analyzed by performing homology search for finding ndh specific conserved domains using conserved domain search. We report the presence of non-functional plastid ndh gene fragments, excepting ndhE and ndhG genes, in the nuclear genome of Norway spruce. Regulatory transcriptional elements like promoters, TATA boxes and enhancers were detected in the upstream regions of some ndh fragments. We also found transposable elements in the flanking regions of few ndh fragments suggesting nuclear rearrangements in those regions. These evidences support the hypothesis that, at least in Picea, ndh translocations from the plastid to the nuclear genome have occurred, and that there might have been a functional machinery at some time during evolution to accommodate them within a nuclear-encoded environment, or attempts to form it.
de las Heras, Jose I.; Czapiewski, Rafal; Sivakumar, Aishwarya; Kerr, Alastair R.W.; Schirmer, Eric C.
2017-01-01
The 3D organization of the genome changes concomitantly with expression changes during hematopoiesis and immune activation. Studies have focused either on lamina-associated domains (LADs) or on topologically associated domains (TADs), defined by preferential local chromatin interactions, and chromosome compartments, defined as higher-order interactions between TADs sharing functionally similar states. However, few studies have investigated how these affect one another. To address this, we mapped LADs using Lamin B1–DamID during Jurkat T-cell activation, finding significant genome reorganization at the nuclear periphery dominated by release of loci frequently important for T-cell function. To assess how these changes at the nuclear periphery influence wider genome organization, our DamID data sets were contrasted with TADs and compartments. Features of specific repositioning events were then tested by fluorescence in situ hybridization during T-cell activation. First, considerable overlap between TADs and LADs was observed with the TAD repositioning as a unit. Second, A1 and A2 subcompartments are segregated in 3D space through differences in proximity to LADs along chromosomes. Third, genes and a putative enhancer in LADs that were released from the periphery during T-cell activation became preferentially associated with A2 subcompartments and were constrained to the relative proximity of the lamina. Thus, lamina associations influence internal nuclear organization, and changes in LADs during T-cell activation may provide an important additional mode of gene regulation. PMID:28424353
Field, Mark C.; Adung’a, Vincent; Obado, Samson; Chait, Brian T.; Rout, Michael P.
2014-01-01
SUMMERY Trypanosomatids represent the causative agents of major diseases in humans, livestock and plants, with inevitable suffering and economic hardship as a result. They are also evolutionarily highly divergent organisms, and the many unique aspects of trypanosome biology provide opportunities in terms of identification of drug targets, the challenge of exploiting these putative targets, and at the same time significant scope for exploration of novel and divergent cell biology. We can estimate from genome sequences that the degree of divergence of trypanosomes from animals and fungi is extreme, with perhaps one third to one half of predicted trypanosome proteins having no known function based on homology or recognizable protein domains/architecture. Two highly important aspects of trypanosome biology are the flagellar pocket and the nuclear envelope, where in silico analysis clearly suggests great potential divergence in the proteome. The flagellar pocket is the sole site of endo- and exocytosis in trypanosomes and plays important roles in immune evasion via variant surface glycoprotein (VSG) trafficking and providing a location for sequestration of various invariant receptors. The trypanosome nuclear envelope has been largely unexplored, but by analogy with higher eukaryotes, roles in the regulation of chromatin and most significantly, in controlling VSG gene expression are expected. Here we discuss recent successful proteomics-based approaches towards characterization of the nuclear envelope and the endocytic apparatus, the identification of conserved and novel trypanosomatid-specific features, and the implications of these findings. PMID:22309600
Unraveling Genetic Modifiers in the Gria4 Mouse Model of Absence Epilepsy
Frankel, Wayne N.; Mahaffey, Connie L.; McGarr, Tracy C.; Beyer, Barbara J.; Letts, Verity A.
2014-01-01
Absence epilepsy (AE) is a common type of genetic generalized epilepsy (GGE), particularly in children. AE and GGE are complex genetic diseases with few causal variants identified to date. Gria4 deficient mice provide a model of AE, one for which the common laboratory inbred strain C3H/HeJ (HeJ) harbors a natural IAP retrotransposon insertion in Gria4 that reduces its expression 8-fold. Between C3H and non-seizing strains such as C57BL/6, genetic modifiers alter disease severity. Even C3H substrains have surprising variation in the duration and incidence of spike-wave discharges (SWD), the characteristic electroencephalographic feature of absence seizures. Here we discovered extensive IAP retrotransposition in the C3H substrain, and identified a HeJ-private IAP in the Pcnxl2 gene, which encodes a putative multi-transmembrane protein of unknown function, resulting in decreased expression. By creating new Pcnxl2 frameshift alleles using TALEN mutagenesis, we show that Pcnxl2 deficiency is responsible for mitigating the seizure phenotype – making Pcnxl2 the first known modifier gene for absence seizures in any species. This finding gave us a handle on genetic complexity between strains, directing us to use another C3H substrain to map additional modifiers including validation of a Chr 15 locus that profoundly affects the severity of SWD episodes. Together these new findings expand our knowledge of how natural variation modulates seizures, and highlights the feasibility of characterizing and validating modifiers in mouse strains and substrains in the post-genome sequence era. PMID:25010494
An effect of nuclear electric quadrupole moments in thermonuclear fusion plasmas
NASA Technical Reports Server (NTRS)
De, B. R.; Srnka, L. J.
1978-01-01
Consideration of the nuclear electric quadrupole terms in the expression for the fusion Coulomb barrier suggests that this electrostatic barrier may be substantially modified from that calculated under the usual plasma assumption that the nuclei are electric monopoles. This effect is a result of the nonspherical potential shape and the spatial quantization of the nuclear spins of the fully stripped ions in the presence of a magnetic field. For monopole-quadrupole fuel cycles like p-B-11, the fusion cross-section may be substantially increased at low energies if the protons are injected at a small angle relative to the confining magnetic field.
NASA Astrophysics Data System (ADS)
Mäntysaari, Heikki; Venugopalan, Raju
2018-06-01
We show that gluon saturation gives rise to a strong modification of the scaling in both the nuclear mass number A and the virtuality Q2 of the vector meson production cross-section in exclusive deep-inelastic scattering off nuclei. We present qualitative analytic expressions for how the scaling exponents are modified as well as quantitative predictions that can be tested at an Electron-Ion Collider.
Ng, Yee-Hong; Bettens, Ryan P A
2016-03-03
Using the method of modified Shepard's interpolation to construct potential energy surfaces of the H2O, O3, and HCOOH molecules, we compute vibrationally averaged isotropic nuclear shielding constants ⟨σ⟩ of the three molecules via quantum diffusion Monte Carlo (QDMC). The QDMC results are compared to that of second-order perturbation theory (PT), to see if second-order PT is adequate for obtaining accurate values of nuclear shielding constants of molecules with large amplitude motions. ⟨σ⟩ computed by the two approaches differ for the hydrogens and carbonyl oxygen of HCOOH, suggesting that for certain molecules such as HCOOH where big displacements away from equilibrium happen (internal OH rotation), ⟨σ⟩ of experimental quality may only be obtainable with the use of more sophisticated and accurate methods, such as quantum diffusion Monte Carlo. The approach of modified Shepard's interpolation is also extended to construct shielding constants σ surfaces of the three molecules. By using a σ surface with the equilibrium geometry as a single data point to compute isotropic nuclear shielding constants for each descendant in the QDMC ensemble representing the ground state wave function, we reproduce the results obtained through ab initio computed σ to within statistical noise. Development of such an approach could thereby alleviate the need for any future costly ab initio σ calculations.
Decoding the network of Trypanosoma brucei proteins that determines sensitivity to apolipoprotein-L1
MacLeod, Annette
2018-01-01
In contrast to Trypanosoma brucei gambiense and T. b. rhodesiense (the causative agents of human African trypanosomiasis), T. b. brucei is lysed by apolipoprotein-L1 (apoL1)-containing human serum trypanolytic factors (TLF), rendering it non-infectious to humans. While the mechanisms of TLF1 uptake, apoL1 membrane integration, and T. b. gambiense and T. b. rhodesiense apoL1-resistance have been extensively characterised, our understanding of the range of factors that drive apoL1 action in T. b. brucei is limited. Selecting our bloodstream-form T. b. brucei RNAi library with recombinant apoL1 identified an array of factors that supports the trypanocidal action of apoL1, including six putative ubiquitin modifiers and several proteins putatively involved in membrane trafficking; we also identified the known apoL1 sensitivity determinants, TbKIFC1 and the V-ATPase. Most prominent amongst the novel apoL1 sensitivity determinants was a putative ubiquitin ligase. Intriguingly, while loss of this ubiquitin ligase reduces parasite sensitivity to apoL1, its loss enhances parasite sensitivity to TLF1-dominated normal human serum, indicating that free and TLF1-bound apoL1 have contrasting modes-of-action. Indeed, loss of the known human serum sensitivity determinants, p67 (lysosomal associated membrane protein) and the cathepsin-L regulator, ‘inhibitor of cysteine peptidase’, had no effect on sensitivity to free apoL1. Our findings highlight a complex network of proteins that influences apoL1 action, with implications for our understanding of the anti-trypanosomal action of human serum. PMID:29346416
Cattaruzza, Sabrina; Nicolosi, Pier Andrea; Braghetta, Paola; Pazzaglia, Laura; Benassi, Maria Serena; Picci, Piero; Lacrima, Katia; Zanocco, Daniela; Rizzo, Erika; Stallcup, William B; Colombatti, Alfonso; Perris, Roberto
2013-06-01
In soft-tissue sarcoma patients, enhanced expression of NG2/CSPG4 proteoglycan in pre-surgical primary tumours predicts post-surgical metastasis formation and thereby stratifies patients into disease-free survivors and patients destined to succumb to the disease. Both primary and secondary sarcoma lesions also up-regulate collagen type VI, a putative extracellular matrix ligand of NG2, and this matrix alteration potentiates the prognostic impact of NG2. Enhanced constitutive levels of the proteoglycan in isolated sarcoma cells closely correlate with a superior engraftment capability and local growth in xenogenic settings. This apparent NG2-associated malignancy was also corroborated by the diverse tumorigenic behaviour in vitro and in vivo of immunoselected NG2-expressing and NG2-deficient cell subsets, by RNAi-mediated knock down of endogenous NG2, and by ectopic transduction of full-length or deletion constructs of NG2. Cells with modified expression of NG2 diverged in their interaction with purified Col VI, matrices supplemented with Col VI, and cell-free matrices isolated from wild-type and Col VI null fibroblasts. The combined use of dominant-negative NG2 mutant cells and purified domain fragments of the collagen allowed us to pinpoint the reciprocal binding sites within the two molecules and to assert the importance of this molecular interaction in the control of sarcoma cell adhesion and motility. The NG2-mediated binding to Col VI triggered activation of convergent cell survival- and cell adhesion/migration-promoting signal transduction pathways, implicating PI-3K as a common denominator. Thus, the findings point to an NG2-Col VI interplay as putatively involved in the regulation of the cancer cell-host microenvironment interactions sustaining sarcoma progression.
Xu, Jingyu; Francis, Tammy; Mietkiewska, Elzbieta; Giblin, E Michael; Barton, Dennis L; Zhang, Yan; Zhang, Meng; Taylor, David C
2008-10-01
A full-length cDNA encoding a putative diacylglycerol acyltransferase 1 (DGAT1, EC 2.3.1.20) was obtained from Tropaeolum majus (garden nasturtium). The 1557-bp open reading frame of this cDNA, designated TmDGAT1, encodes a protein of 518 amino acids showing high homology to other plant DGAT1s. The TmDGAT1 gene was expressed exclusively in developing seeds. Expression of recombinant TmDGAT1 in the yeast H1246MATalpha quadruple mutant (DGA1, LRO1, ARE1, ARE2) restored the capability of the mutant host to produce triacylglycerols (TAGs). The recombinant TmDGAT1 protein was capable of utilizing a range of (14)C-labelled fatty acyl-CoA donors and diacylglycerol acceptors, and could synthesize (14)C-trierucin. Collectively, these findings confirm that the TmDGAT1 gene encodes an acyl-CoA-dependent DGAT1. In plant transformation studies, seed-specific expression of TmDGAT1 was able to complement the low TAG/unusual fatty acid phenotype of the Arabidopsis AS11 (DGAT1) mutant. Over-expression of TmDGAT1 in wild-type Arabidopsis and high-erucic-acid rapeseed (HEAR) and canola Brassica napus resulted in an increase in oil content (3.5%-10% on a dry weight basis, or a net increase of 11%-30%). Site-directed mutagenesis was conducted on six putative functional regions/motifs of the TmDGAT1 enzyme. Mutagenesis of a serine residue in a putative SnRK1 target site resulted in a 38%-80% increase in DGAT1 activity, and over-expression of the mutated TmDGAT1 in Arabidopsis resulted in a 20%-50% increase in oil content on a per seed basis. Thus, alteration of this putative serine/threonine protein kinase site can be exploited to enhance DGAT1 activity, and expression of mutated DGAT1 can be used to enhance oil content.
Hypoxia modifies nuclear calcium uptake pathways in the cerebral cortex of the guinea-pig fetus.
Zanelli, S A; Spandou, E; Mishra, O P; Delivoria-Papadopoulos, M
2005-01-01
Nuclear Ca2+ signals are thought to play a critical role in the initiation and progression of programmed cell death. The present study tests the hypothesis that hypoxia alters nuclear Ca2+ transport pathways and leads to an increase in nuclear Ca(2+)-influx in cerebral cortical neuronal nuclei. To test this hypothesis the effect of tissue hypoxia on high affinity Ca(2+)-ATPase activity and the binding characteristics of inositol 1,4,5-triphosphate (IP3) and inositol 1,3,4,5-tetrakisphosphate (IP4) receptors were studied in neuronal nuclei from the cerebral cortex of guinea-pig fetuses. Results show increased high-affinity Ca(2+)-ATPase activity (nmol/mg protein/h) in the hypoxic group 969.7+/-79 as compared with 602.4+/-90.9 in the normoxic group, P<0.05. The number of IP3 receptors (Bmax, fmol/mg protein) increased from 61+/-21 in the normoxic group to 164+/-49 in the hypoxic group, P<0.05. K(d) values did not change following hypoxia. In contrast, IP4 receptor Bmax (fmol/mg protein) and K(d) (nM) values increased from 360+/-32 in the normoxic group to 626+/-136 in the hypoxic group (P<0.001) and, from 26+/-1 in the normoxic group to 61+/-9 in the hypoxic group (P<0.001), respectively. 45Ca(2+)-influx (pmol/mg protein) significantly increased from 6.3+/-1.9 in the normoxic group to 10.9+/-1.1 the hypoxic group (P<0.001). The data show that hypoxia modifies nuclear Ca2+ transport pathways and results in increased nuclear Ca(2+)-influx. We speculate that hypoxia increases nuclear Ca2+ uptake from the cytoplasm to the nucleoplasm, resulting in increased transcription of proapoptotic genes and subsequent activation of programmed cell death pathways.
Jarjies, Adnan; Abbas, Mohammed; Monken Fernandes, Horst; Wong, Melanie; Coates, Roger
2013-05-01
There are a number of sites in Iraq which have been used for nuclear activities and which contain potentially significant amounts of radioactive waste. The principal nuclear site being Al-Tuwaitha. Many of these sites suffered substantial physical damage during the Gulf Wars and have been subjected to subsequent looting. All require decommissioning in order to ensure both radiological and non-radiological safety. However, it is not possible to undertake the decommissioning of all sites and facilities at the same time. Therefore, a prioritization methodology has been developed in order to aid the decision-making process. The methodology comprises three principal stages of assessment: i) a quantitative surrogate risk assessment ii) a range of sensitivity analyses and iii) the inclusion of qualitative modifying factors. A group of Tuwaitha facilities presented the highest risk among the evaluated ones, followed by a middle ranking grouping of Tuwaitha facilities and some other sites, and a relatively large group of lower risk facilities and sites. The initial order of priority is changed when modifying factors are taken into account. It has to be considered the Iraq's isolation from the international nuclear community over the last two decades and the lack of experienced personnel. Therefore it is appropriate to initiate decommissioning operations on selected low risk facilities at Tuwaitha in order to build capacity and prepare for work to be carried out in more complex and potentially high hazard facilities. In addition it is appropriate to initiate some prudent precautionary actions relating to some of the higher risk facilities. Copyright © 2012 Elsevier Ltd. All rights reserved.
Dynamic assembly of brambleberry mediates nuclear envelope fusion during early development.
Abrams, Elliott W; Zhang, Hong; Marlow, Florence L; Kapp, Lee; Lu, Sumei; Mullins, Mary C
2012-08-03
To accommodate the large cells following zygote formation, early blastomeres employ modified cell divisions. Karyomeres are one such modification, mitotic intermediates wherein individual chromatin masses are surrounded by nuclear envelope; the karyomeres then fuse to form a single mononucleus. We identified brambleberry, a maternal-effect zebrafish mutant that disrupts karyomere fusion, resulting in formation of multiple micronuclei. As karyomeres form, Brambleberry protein localizes to the nuclear envelope, with prominent puncta evident near karyomere-karyomere interfaces corresponding to membrane fusion sites. brambleberry corresponds to an unannotated gene with similarity to Kar5p, a protein that participates in nuclear fusion in yeast. We also demonstrate that Brambleberry is required for pronuclear fusion following fertilization in zebrafish. Our studies provide insight into the machinery required for karyomere fusion and suggest that specialized proteins are necessary for proper nuclear division in large dividing blastomeres. Copyright © 2012 Elsevier Inc. All rights reserved.
Metcalf, Jessica L; Pritchard, Victoria L; Silvestri, Sarah M; Jenkins, Jazzmin B; Wood, John S; Cowley, David E; Evans, R Paul; Shiozawa, Dennis K; Martin, Andrew P
2007-11-01
Accurate assessment of species identity is fundamental for conservation biology. Using molecular markers from the mitochondrial and nuclear genomes, we discovered that many putatively native populations of greenback cutthroat trout (Oncorhynchus clarkii stomias) comprised another subspecies of cutthroat trout, Colorado River cutthroat trout (Oncorhynchus clarkii pleuriticus). The error can be explained by the introduction of Colorado River cutthroat trout throughout the native range of greenback cutthroat trout in the late 19th and early 20th centuries by fish stocking activities. Our results suggest greenback cutthroat trout within its native range is at a higher risk of extinction than ever before despite conservation activities spanning more than two decades.
Markina-Iñarrairaegui, Ane; Etxebeste, Oier; Herrero-García, Erika; Araújo-Bazán, Lidia; Fernández-Martínez, Javier; Flores, Jairo A.; Osmani, Stephen A.; Espeso, Eduardo A.
2011-01-01
Nuclear transporters mediate bidirectional macromolecule traffic through the nuclear pore complex (NPC), thus participating in vital processes of eukaryotic cells. A systematic functional analysis in Aspergillus nidulans permitted the identification of 4 essential nuclear transport pathways of a hypothetical number of 14. The absence of phenotypes for most deletants indicates redundant roles for these nuclear receptors. Subcellular distribution studies of these carriers show three main distributions: nuclear, nucleocytoplasmic, and in association with the nuclear envelope. These locations are not specific to predicted roles as exportins or importins but indicate that bidirectional transport may occur coordinately in all nuclei of a syncytium. Coinciding with mitotic NPC rearrangements, transporters dynamically modified their localizations, suggesting supplementary roles to nucleocytoplasmic transport specifically during mitosis. Loss of transportin-SR and Mex/TAP from the nuclear envelope indicates absence of RNA transport during the partially open mitosis of Aspergillus, whereas nucleolar accumulation of Kap121 and Kap123 homologues suggests a role in nucleolar disassembly. This work provides new insight into the roles of nuclear transporters and opens an avenue for future studies of the molecular mechanisms of transport among nuclei within a common cytoplasm, using A. nidulans as a model organism. PMID:21880896
N-Glycopeptide Profiling in Arabidopsis Inflorescence
Xu, Shou-Ling; Medzihradszky, Katalin F.; Wang, Zhi-Yong; ...
2016-04-11
This study presents the first large scale analysis of plant intact glycopeptides. Using wheat germ agglutinin lectin weak affinity chromatography to enrich modified peptides, followed by ETD fragmentation tandem mass spectrometry, glycan compositions on over 1100 glycopeptides from 270 proteins found in Arabidopsis inflorescence tissue were characterized. While some sites were only detected with a single glycan attached, others displayed up to 16 different glycoforms. Among the identified glycopeptides were four modified in non-consensus glycosylation motifs. Finally, while most of the modified proteins are secreted, membrane, ER or Golgi localized proteins, surprisingly N-linked sugars were detected on a protein predictedmore » to be cytosolic or nuclear.« less
Production of healthy cloned mice from bodies frozen at -20 degrees C for 16 years.
Wakayama, Sayaka; Ohta, Hiroshi; Hikichi, Takafusa; Mizutani, Eiji; Iwaki, Takamasa; Kanagawa, Osami; Wakayama, Teruhiko
2008-11-11
Cloning animals by nuclear transfer provides an opportunity to preserve endangered mammalian species. However, it has been suggested that the "resurrection" of frozen extinct species (such as the woolly mammoth) is impracticable, as no live cells are available, and the genomic material that remains is inevitably degraded. Here we report production of cloned mice from bodies kept frozen at -20 degrees C for up to 16 years without any cryoprotection. As all of the cells were ruptured after thawing, we used a modified cloning method and examined nuclei from several organs for use in nuclear transfer attempts. Using brain nuclei as nuclear donors, we established embryonic stem cell lines from the cloned embryos. Healthy cloned mice were then produced from these nuclear transferred embryonic stem cells by serial nuclear transfer. Thus, nuclear transfer techniques could be used to "resurrect" animals or maintain valuable genomic stocks from tissues frozen for prolonged periods without any cryopreservation.
Production of healthy cloned mice from bodies frozen at −20°C for 16 years
Wakayama, Sayaka; Ohta, Hiroshi; Hikichi, Takafusa; Mizutani, Eiji; Iwaki, Takamasa; Kanagawa, Osami; Wakayama, Teruhiko
2008-01-01
Cloning animals by nuclear transfer provides an opportunity to preserve endangered mammalian species. However, it has been suggested that the “resurrection” of frozen extinct species (such as the woolly mammoth) is impracticable, as no live cells are available, and the genomic material that remains is inevitably degraded. Here we report production of cloned mice from bodies kept frozen at −20 °C for up to 16 years without any cryoprotection. As all of the cells were ruptured after thawing, we used a modified cloning method and examined nuclei from several organs for use in nuclear transfer attempts. Using brain nuclei as nuclear donors, we established embryonic stem cell lines from the cloned embryos. Healthy cloned mice were then produced from these nuclear transferred embryonic stem cells by serial nuclear transfer. Thus, nuclear transfer techniques could be used to “resurrect” animals or maintain valuable genomic stocks from tissues frozen for prolonged periods without any cryopreservation. PMID:18981419
Genome-nuclear lamina interactions and gene regulation.
Kind, Jop; van Steensel, Bas
2010-06-01
The nuclear lamina, a filamentous protein network that coats the inner nuclear membrane, has long been thought to interact with specific genomic loci and regulate their expression. Molecular mapping studies have now identified large genomic domains that are in contact with the lamina. Genes in these domains are typically repressed, and artificial tethering experiments indicate that the lamina can actively contribute to this repression. Furthermore, the lamina indirectly controls gene expression in the nuclear interior by sequestration of certain transcription factors. A variety of DNA-binding and chromatin proteins may anchor specific loci to the lamina, while histone-modifying enzymes partly mediate the local repressive effect of the lamina. Experimental tools are now available to begin to unravel the underlying molecular mechanisms. Copyright 2010 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pruet, J
2007-06-23
This report describes Kiwi, a program developed at Livermore to enable mature studies of the relation between imperfectly known nuclear physics and uncertainties in simulations of complicated systems. Kiwi includes a library of evaluated nuclear data uncertainties, tools for modifying data according to these uncertainties, and a simple interface for generating processed data used by transport codes. As well, Kiwi provides access to calculations of k eigenvalues for critical assemblies. This allows the user to check implications of data modifications against integral experiments for multiplying systems. Kiwi is written in python. The uncertainty library has the same format and directorymore » structure as the native ENDL used at Livermore. Calculations for critical assemblies rely on deterministic and Monte Carlo codes developed by B division.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gajski, Goran; Garaj-Vrhovac, Vera; Orescanin, Visnja
2008-08-15
To investigate the genotoxic potential of atorvastatin on human lymphocytes in vitro standard comet assay was used in the evaluation of basal DNA damage and to investigate possible oxidative DNA damage produced by reactive oxygen species (ROS) Fpg-modified version of comet assay was also conducted. In addition to these techniques the new criteria for scoring micronucleus test were applied for more complete detection of baseline damage in binuclear lymphocytes exposed to atorvastatin 80 mg/day in different time periods by virtue of measuring the frequency of micronuclei, nucleoplasmic bridges and nuclear buds. All parameters obtained with the standard comet assay andmore » Fpg-modified comet assay were significantly higher in the treated than in control lymphocytes. The Fpg-modified comet assay showed a significantly greater tail length, tail intensity, and tail moment in all treated lymphocytes than did the standard comet assay, which suggests that oxidative stress is likely to be responsible for DNA damage. DNA damage detected by the standard comet assay indicates that some other mechanism is also involved. In addition to the comet assay, a total number of micronuclei, nucleoplasmic bridges and nuclear buds were significantly higher in the exposed than in controlled lymphocytes. Regression analyses showed a positive correlation between the results obtained by the comet (Fpg-modified and standard) and micronucleus assay. Overall, the study demonstrated that atorvastatin in its highest dose is capable of producing damage on the level of DNA molecule and cell.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Phrakonkham, Pascal; Chevalier, Joelle; Desmetz, Catherine
2007-10-15
The use of soy isoflavones is a potential alternative to hormone replacement therapy in post-menopausal bone-loss prevention. Nevertheless, phytoestrogens can target other organs and may disrupt cell proliferation, or could modify endogenous steroid hormone metabolism. These mechanisms could be linked to an increased risk of developing cancer. We therefore studied the possible side effects of such treatments in an experimental model of menopause. Forty adult female Wistar rats were ovariectomized and fed with a genistein-, daidzein- or equol-supplemented diet at bone-sparing levels (10 mg/kg BW/day) for 3 months. The estrogenic effects were assessed by histological and molecular analyses on reproductivemore » organs. The impact on the oxidative metabolism of estradiol and on associated cytochrome P450 (CYP) activities was evaluated in liver microsomes. The relative wet weights of both the uterus and the vagina were increased in the equol group, but no significant changes in proliferating cell nuclear antigen or hormone receptor mRNA expression were noticed. In contrast, genistein and daidzein did not induce uterotrophy but caused an overexpression of estrogen receptor {alpha} mRNA which could correspond to a long-lasting effect of physiological concentrations of estrogens. The hepatic metabolism of estradiol was influenced by daidzein which increased the synthesis of putative mutagenic derivatives. At the same time, genistein favored estrogen 2-hydroxylation, and equol decreased 4-hydroxyestrogen production. Surprisingly, no significant alteration in hepatic CYP activities was detected. Taken together, these results demonstrate that isoflavonoid-based bone-sparing treatments are able to cause side effects on other estrogen-sensitive target organs when given in the long-term.« less
Engineering low-cadmium rice through stress-inducible expression of OXS3-family member genes.
Wang, Changhu; Guo, Weili; Cai, Xingzhe; Li, Ruyu; Ow, David W
2018-04-21
Cadmium (Cd) as a carcinogen poses a great threat to food security and public health through plant-derived foods such as rice, the staple for nearly half of the world's population. We have previously reported that overexpression of truncated gene fragments derived from the rice genes OsO3L2 and OsO3L3 could reduce Cd accumulation in transgenic rice. However, we did not test the full length genes due to prior work in Arabidopsis where overexpression of these genes caused seedling lethality. Here, we report on limiting the overexpression of OsO3L2 and OsO3L3 through the use of the stress- inducible promoter RD29B. However, despite generating 625 putative transformants, only 7 lines survived as T1 seedlings and only 1 line of each overexpressed OsO3L2 or OsO3L3-produced T2 progeny. The T2 homozygotes from these 2 lines showed the same effect of reducing accumulation of Cd in root and shoot as well as in T3 grain. As importantly, the concentrations of essential metals copper (Cu), iron (Fe), manganese (Mn) and zinc (Zn) were unaffected. Analysis of the expression profile suggested that low Cd accumulation may be due to high expression of OsO3L2 and OsO3L3 in the root tip region. Cellular localization of OsO3L2 and OsO3L3 indicate that they are histone H2A interacting nuclear proteins in vascular cells and especially in the root tip region. It is possible that interaction with histone H2A modifies chromatin to regulate downstream gene expression. Copyright © 2018. Published by Elsevier B.V.
Husari, Ayman; Hülter-Hassler, Diana; Steinberg, Thorsten; Schulz, Simon Daniel; Tomakidi, Pascal
2018-01-01
Accumulating evidences indicate that alcohol might play a causative in oral cancer. Unfortunately, in vitro cell systems, uncovering the molecular background of the underlying cell transformation process, are rare. Therefore, this study was conducted, to identify molecular changes and characterize their putative cell behavioral consequences in epitheloid (EPI) and fibroblastoid (FIB) oral keratinocyte phenotypes, arising from chronical alcohol treatment. Concerning adherens junctions (AJs), both EPI and FIB showed membrane-bound β-catenin, but exhibited differences for E-cadherin and zyxin. While EPI revealed E-cadherin/β-catenin membrane co-localization, which in parts also applied for zyxin, FIB membranes were devoid of E-cadherin and exhibited marginal zyxin expression. Fetal calf serum (FCS) administration in starved cells promoted proliferation in both keratinocyte phenotypes, whereat EPI and FIB yielded a strikingly modified FCS sensitivity on the temporal scale. Impedance measurement-based cell index detection yielded proliferation stimulation occurring much earlier in FIB (<20h) compared to EPI (>45h). Nuclear preference of the proliferation-associated YAP co-transcription factor in FIB was FCS independent, while it required FCS in EPI. Taken together, the lack of membrane-inherent E-cadherin/β-catenin co-localization together with low zyxin - reveals perturbation of AJ integrity in FIB. Regarding cell behavior, perturbed AJs in FIB correlate with temporal proliferation sensitivity towards FCS. CYF of 5.6 strongly suggests involvement of chromatin-bound YAP in FIB's proliferation temperosensitivity. These molecular differences detected for EPI and FIB are part of the underlying cell transformation process of alcohol-induced oral carcinogenesis, and indicate FIB being in a more advanced transformation stage. Copyright © 2017 Elsevier B.V. All rights reserved.
Akbari, Omar S; Antoshechkin, Igor; Hay, Bruce A; Ferree, Patrick M
2013-09-04
A widespread phenomenon in nature is sex ratio distortion of arthropod populations caused by microbial and genetic parasites. Currently little is known about how these agents alter host developmental processes to favor one sex or the other. The paternal sex ratio (PSR) chromosome is a nonessential, paternally transmitted centric fragment that segregates in natural populations of the jewel wasp, Nasonia vitripennis. To persist, PSR is thought to modify the hereditary material of the developing sperm, with the result that all nuclear DNA other than the PSR chromosome is destroyed shortly after fertilization. This results in the conversion of a fertilized embryo--normally a female--into a male, thereby insuring transmission of the "selfish" PSR chromosome, and simultaneously leading to wasp populations that are male-biased. To begin to understand this system at the mechanistic level, we carried out transcriptional profiling of testis from WT and PSR-carrying males. We identified a number of transcripts that are differentially expressed between these conditions. We also discovered nine transcripts that are uniquely expressed from the PSR chromosome. Four of these PSR-specific transcripts encode putative proteins, whereas the others have very short open reading frames and no homology to known proteins, suggesting that they are long noncoding RNAs. We propose several different models for how these transcripts could facilitate PSR-dependent effects. Our analyses also revealed 15.71 MB of novel transcribed regions in the N. vitripennis genome, thus increasing the current annotation of total transcribed regions by 53.4%. Finally, we detected expression of multiple meiosis-related genes in the wasp testis, despite the lack of conventional meiosis in the male sex.
Akbari, Omar S.; Antoshechkin, Igor; Hay, Bruce A.; Ferree, Patrick M.
2013-01-01
A widespread phenomenon in nature is sex ratio distortion of arthropod populations caused by microbial and genetic parasites. Currently little is known about how these agents alter host developmental processes to favor one sex or the other. The paternal sex ratio (PSR) chromosome is a nonessential, paternally transmitted centric fragment that segregates in natural populations of the jewel wasp, Nasonia vitripennis. To persist, PSR is thought to modify the hereditary material of the developing sperm, with the result that all nuclear DNA other than the PSR chromosome is destroyed shortly after fertilization. This results in the conversion of a fertilized embryo—normally a female—into a male, thereby insuring transmission of the “selfish” PSR chromosome, and simultaneously leading to wasp populations that are male-biased. To begin to understand this system at the mechanistic level, we carried out transcriptional profiling of testis from WT and PSR-carrying males. We identified a number of transcripts that are differentially expressed between these conditions. We also discovered nine transcripts that are uniquely expressed from the PSR chromosome. Four of these PSR-specific transcripts encode putative proteins, whereas the others have very short open reading frames and no homology to known proteins, suggesting that they are long noncoding RNAs. We propose several different models for how these transcripts could facilitate PSR-dependent effects. Our analyses also revealed 15.71 MB of novel transcribed regions in the N. vitripennis genome, thus increasing the current annotation of total transcribed regions by 53.4%. Finally, we detected expression of multiple meiosis-related genes in the wasp testis, despite the lack of conventional meiosis in the male sex. PMID:23893741
RNA Editing During Sexual Development Occurs in Distantly Related Filamentous Ascomycetes
Teichert, Ines; Dahlmann, Tim A.; Kück, Ulrich
2017-01-01
RNA editing is a post-transcriptional process that modifies RNA molecules leading to transcript sequences that differ from their template DNA. A-to-I editing was found to be widely distributed in nuclear transcripts of metazoa, but was detected in fungi only recently in a study of the filamentous ascomycete Fusarium graminearum that revealed extensive A-to-I editing of mRNAs in sexual structures (fruiting bodies). Here, we searched for putative RNA editing events in RNA-seq data from Sordaria macrospora and Pyronema confluens, two distantly related filamentous ascomycetes, and in data from the Taphrinomycete Schizosaccharomyces pombe. Like F. graminearum, S. macrospora is a member of the Sordariomycetes, whereas P. confluens belongs to the early-diverging group of Pezizomycetes. We found extensive A-to-I editing in RNA-seq data from sexual mycelium from both filamentous ascomycetes, but not in vegetative structures. A-to-I editing was not detected in different stages of meiosis of S. pombe. A comparison of A-to-I editing in S. macrospora with F. graminearum and P. confluens, respectively, revealed little conservation of individual editing sites. An analysis of RNA-seq data from two sterile developmental mutants of S. macrospora showed that A-to-I editing is strongly reduced in these strains. Sequencing of cDNA fragments containing more than one editing site from P. confluens showed that at the beginning of sexual development, transcripts were incompletely edited or unedited, whereas in later stages transcripts were more extensively edited. Taken together, these data suggest that A-to-I RNA editing is an evolutionary conserved feature during fruiting body development in filamentous ascomycetes. PMID:28338982
RNA Editing During Sexual Development Occurs in Distantly Related Filamentous Ascomycetes.
Teichert, Ines; Dahlmann, Tim A; Kück, Ulrich; Nowrousian, Minou
2017-04-01
RNA editing is a post-transcriptional process that modifies RNA molecules leading to transcript sequences that differ from their template DNA. A-to-I editing was found to be widely distributed in nuclear transcripts of metazoa, but was detected in fungi only recently in a study of the filamentous ascomycete Fusarium graminearum that revealed extensive A-to-I editing of mRNAs in sexual structures (fruiting bodies). Here, we searched for putative RNA editing events in RNA-seq data from Sordaria macrospora and Pyronema confluens, two distantly related filamentous ascomycetes, and in data from the Taphrinomycete Schizosaccharomyces pombe. Like F. graminearum, S. macrospora is a member of the Sordariomycetes, whereas P. confluens belongs to the early-diverging group of Pezizomycetes. We found extensive A-to-I editing in RNA-seq data from sexual mycelium from both filamentous ascomycetes, but not in vegetative structures. A-to-I editing was not detected in different stages of meiosis of S. pombe. A comparison of A-to-I editing in S. macrospora with F. graminearum and P. confluens, respectively, revealed little conservation of individual editing sites. An analysis of RNA-seq data from two sterile developmental mutants of S. macrospora showed that A-to-I editing is strongly reduced in these strains. Sequencing of cDNA fragments containing more than one editing site from P. confluens showed that at the beginning of sexual development, transcripts were incompletely edited or unedited, whereas in later stages transcripts were more extensively edited. Taken together, these data suggest that A-to-I RNA editing is an evolutionary conserved feature during fruiting body development in filamentous ascomycetes. © The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.
Modifier cation effects on 29Si nuclear shielding anisotropies in silicate glasses
NASA Astrophysics Data System (ADS)
Baltisberger, Jay H.; Florian, Pierre; Keeler, Eric G.; Phyo, Pyae A.; Sanders, Kevin J.; Grandinetti, Philip J.
2016-07-01
We have examined variations in the 29Si nuclear shielding tensor parameters of SiO4 tetrahedra in a series of seven alkali and alkaline earth silicate glass compositions, Cs2O · 4.81 SiO2, Rb2O · 3.96 SiO2, Rb2O · 2.25 SiO2, K2O · 4.48 SiO2, Na2O · 4.74 SiO2, BaO · 2.64 SiO2, and SrO · 2.36 SiO2, using natural abundance 29Si two-dimensional magic-angle flipping (MAF) experiments. Our analyses of these 2D spectra reveal a linear dependence of the 29Si nuclear shielding anisotropy of Q(3) sites on the Si-non-bridging oxygen bond length, which in turn depends on the cation potential and coordination of modifier cations to the non-bridging oxygen. We also demonstrate how a combination of Cu2+ as a paramagnetic dopant combined with echo train acquisition can reduce the total experiment time of 29Si 2D NMR measurements by two orders of magnitude, enabling higher throughput 2D NMR studies of glass structure.
Modifier cation effects on (29)Si nuclear shielding anisotropies in silicate glasses.
Baltisberger, Jay H; Florian, Pierre; Keeler, Eric G; Phyo, Pyae A; Sanders, Kevin J; Grandinetti, Philip J
2016-07-01
We have examined variations in the (29)Si nuclear shielding tensor parameters of SiO4 tetrahedra in a series of seven alkali and alkaline earth silicate glass compositions, Cs2O·4.81 SiO2, Rb2O·3.96 SiO2, Rb2O·2.25 SiO2, K2O·4.48 SiO2, Na2O·4.74 SiO2, BaO·2.64 SiO2, and SrO·2.36 SiO2, using natural abundance (29)Si two-dimensional magic-angle flipping (MAF) experiments. Our analyses of these 2D spectra reveal a linear dependence of the (29)Si nuclear shielding anisotropy of Q((3)) sites on the Si-non-bridging oxygen bond length, which in turn depends on the cation potential and coordination of modifier cations to the non-bridging oxygen. We also demonstrate how a combination of Cu(2+) as a paramagnetic dopant combined with echo train acquisition can reduce the total experiment time of (29)Si 2D NMR measurements by two orders of magnitude, enabling higher throughput 2D NMR studies of glass structure. Copyright © 2016 Elsevier Inc. All rights reserved.
Fu, Yi-Ping; Yu, Jyh-Cherng; Cheng, Ting-Chih; Lou, M Ann; Hsu, Giu-Cheng; Wu, Chia-Yun; Chen, Sou-Tong; Wu, Hurng-Sheng; Wu, Pei-Ei; Shen, Chen-Yang
2003-05-15
The role of the familial breast cancer susceptibility genes, BRCA1 and BRCA2, in the homologous recombination pathway for DNA double-strand break (DSB) repair suggests that the mechanisms involved in DNA DSB repair are of particular etiological importance during breast tumorigenesis. However, there is currently no evidence for an association between breast cancer and the other DSB repair pathway, the nonhomologous end-joining (NHEJ) pathway. It is possible that, because this DNA repair pathway is so crucial for mammalian cells to maintain genomic stability, any severe defects in it would result in serious outcomes, such as genomic instability and cell death, and block subsequent cell outgrowth and tumor formation. Thus, only subtle defects arising from low-penetrance alleles would escape lethality accumulating essential genetic changes and be associated with cancer formation, and the tumorigenic contribution of these alleles would become more obvious if individual putative high-risk genotypes of each NHEJ gene act jointly. Furthermore, this joint effect might be modified by specific environmental factors, and we hypothesized that estrogen exposure might be one such factor because estrogen is suggested to cause DNA DSBs, triggering breast tumorigenesis. Because single nucleotide polymorphisms (SNPs) are the most subtle genetic variation in the genome, to examine these hypotheses, we have genotyped 30 SNPs in all five NHEJ genes (Ku70, Ku80, DNA-PKcs, Ligase IV, and XRCC4) in 254 primary breast cancer patients and 379 healthy controls. Support for these hypotheses came from the observations that (a) two SNPs in Ku70 and XRCC4 were associated with breast cancer risk (P < 0.05); (b) a trend toward increased risk of developing breast cancer was found in women harboring a greater number of putative high-risk genotypes of NHEJ genes (an adjusted odds ratio of 1.46 for having one additional putative high-risk genotype; 95% confidence interval, 1.19-1.80); (c) this association between risk and the number of putative high-risk genotypes was stronger and more significant in women thought to be more susceptible to estrogen, i.e., those with no history of full-term pregnancy; and (d) the protective effect conferred by a history of full-term pregnancy was only significant in women with a lower number of putative high-risk genotypes of NHEJ genes. Based on comprehensive NHEJ gene profiles, this study provides new insights to suggest the role of the NHEJ pathway in breast cancer development and supports the possibility that breast cancer is initiated by estrogen exposure, which causes DNA DSBs.
Brenet, Fabienne; Dussault, Nadège; Borch, Jonas; Ferracci, Géraldine; Delfino, Christine; Roepstorff, Peter; Miquelis, Raymond; Ouafik, L'Houcine
2005-01-01
Peptidylglycine α-amidating monooxygenase (PAM; EC 1.14.17.3) catalyzes the COOH-terminal α-amidation of peptidylglycine substrates, yielding amidated products. We have previously reported a putative regulatory RNA binding protein (PAM mRNA-BP) that binds specifically to the 3′ untranslated region (UTR) of PAM-mRNA. Here, the PAM mRNA-BP was isolated and revealed to be La protein using affinity purification onto a 3′ UTR PAM RNA, followed by tandem mass spectrometry identification. We determined that the core binding sequence is approximately 15-nucleotides (nt) long and is located 471 nt downstream of the stop codon. Moreover, we identified the La autoantigen as a protein that specifically binds the 3′ UTR of PAM mRNA in vivo and in vitro. Furthermore, La protein overexpression caused a nuclear retention of PAM mRNAs and resulted in the down-regulation of endogenous PAM activity. Most interestingly, the nuclear retention of PAM mRNA is lost upon expressing the La proteins that lack a conserved nuclear retention element, suggesting a direct association between PAM mRNA and La protein in vivo. Reporter assays using a chimeric mRNA that combined luciferase and the 3′ UTR of PAM mRNA demonstrated a decrease of the reporter activity due to an increase in the nuclear localization of reporter mRNAs, while the deletion of the 15-nt La binding site led to their clear-cut cytoplasmic relocalization. The results suggest an important role for the La protein in the modulation of PAM expression, possibly by mechanisms that involve a nuclear retention and perhaps a processing of pre-PAM mRNA molecules. PMID:16107699
EphB4 localises to the nucleus of prostate cancer cells
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mertens-Walker, Inga, E-mail: inga.mertenswalker@qut.edu.au; Australian Prostate Cancer Research Centre—Queensland, Translational Research Institute, 37 Kent Street, Woolloongabba 4102, QLD; Lisle, Jessica E.
2015-04-10
The EphB4 receptor tyrosine kinase is over-expressed in a variety of different epithelial cancers including prostate where it has been shown to be involved in survival, migration and angiogenesis. We report here that EphB4 also resides in the nucleus of prostate cancer cell lines. We used in silico methods to identify a bipartite nuclear localisation signal (NLS) in the extracellular domain and a monopartite NLS sequence in the intracellular kinase domain of EphB4. To determine whether both putative NLS sequences were functional, fragments of the EphB4 sequence containing each NLS were cloned to create EphB4NLS-GFP fusion proteins. Localisation of bothmore » NLS-GFP proteins to the nuclei of transfected cells was observed, demonstrating that EphB4 contains two functional NLS sequences. Mutation of the key amino residues in both NLS sequences resulted in diminished nuclear accumulation. As nuclear translocation is often dependent on importins we confirmed that EphB4 and importin-α can interact. To assess if nuclear EphB4 could be implicated in gene regulatory functions potential EphB4-binding genomic loci were identified using chromatin immunoprecipitation and Lef1 was confirmed as a potential target of EphB4-mediated gene regulation. These novel findings add further complexity to the biology of this important cancer-associated receptor. - Highlights: • The EphB4 protein can be found in the nucleus of prostate cancer cell lines. • EphB4 contains two functional nuclear localisation signals. • Chromatin immunoprecipitation has identified potential genome sequences to which EphB4 binds. • Lef1 is a confirmed target for EphB4-mediated gene regulation.« less
Tsapakidis, Konstantinos; Vlachostergios, Panagiotis J; Voutsadakis, Ioannis A; Befani, Christina D; Patrikidou, Anna; Hatzidaki, Eleana; Daliani, Danai D; Moutzouris, George; Liakos, Panagiotis; Papandreou, Christos N
2012-06-01
Neuropeptides are important signal initiators in advanced prostate cancer, partially acting through activation of nuclear factor kappa B. Central to nuclear factor kappa B regulation is the ubiquitin-proteasome system, pharmacological inhibition of which has been proposed as an anticancer strategy. We investigated the putative role of the proteasome inhibitor bortezomib in neuropeptides signaling effects on prostate cancer cells. Human prostate cancer cell lines, LNCaP and PC-3, were used to examine cell proliferation, levels of proapoptotic (caspase-3, Bad) and cell cycle regulatory proteins (p53, p27, p21), as well as total and phosphorylated Akt and p44/42 mitogen-activated protein kinase proteins. Furthermore, 20S proteasome activity, subcellular localization of nuclear factor kappa B and transcription of nuclear factor kappa B target genes, interleukin-8 and vascular endothelial growth factor, were assessed. Neuropeptides (endothelin-1, bombesin) increased cell proliferation, whereas bortezomib decreased proliferation and induced apoptosis, an effect maintained after cotreatment with neuropeptides. Bad, p53, p21 and p27 were downregulated by neuropeptides in PC-3, and these effects were reversed with the addition of bortezomib. Neuropeptides increased proteasomal activity and nuclear factor kappa B levels in PC-3, and these effects were prevented by bortezomib. Interleukin-8 and vascular endothelial growth factor transcripts were induced after neuropeptides treatment, but downregulated by bortezomib. These results coincided with the ability of bortezomib to reduce mitogen-activated protein kinase signaling in both cell lines. These findings are consistent with bortezomib-mediated abrogation of neuropeptides-induced proliferative and antiapoptotic signaling. Thus, the effect of the drug on the neuropeptides axis needs to be further investigated, as neuropeptide action in prostate cancer might entail involvement of the proteasome. © 2012 The Japanese Urological Association.
NASA Astrophysics Data System (ADS)
Amusia, M. Ya.; Chernysheva, L. V.
2018-01-01
We investigate ground state properties of atoms, in which substitute fermions - electrons by bosons, namely π --mesons. We perform some calculations in the frame of modified Hartree-Fock (HF) equation. The modification takes into account symmetry, instead of anti-symmetry of the pair identical bosons wave function. The modified HF approach thus enhances (doubles) the effect of self-action for the boson case. Therefore, we accordingly modify the HF equations by eliminating the self-action terms "by hand". The contribution of meson-meson and meson-nucleon non-Coulomb interaction is inessential at least for atoms with low and intermediate nuclear charge, which is our main subject. We found that the binding energy of pion negative ions A π - , pion atoms A π , and the number of extra bound pions ΔN π increases with the growth of nuclear charge Z. For e.g. Xe ΔN π = 4. As an example of a simple process with a pion atom, we consider photoionization that differs essentially from that for electron atoms. Namely, it is not monotonic decreasing from the threshold but has instead a prominent maximum above threshold. We study also elastic scattering of pions by pion atoms.
Direct characterization of cotton fabrics treated with di-epoxide by nuclear magnetic resonance.
Xiao, Min; Chéry, Joronia; Keresztes, Ivan; Zax, David B; Frey, Margaret W
2017-10-15
A non-acid-based, di-functional epoxide, neopentyl glycol diglycidyl ether (NPGDGE), was used to modify cotton fabrics. Direct characterization of the modified cotton was conducted by Nuclear Magnetic Resonance (NMR) without grinding the fabric into a fine powder. NaOH and MgBr 2 were compared in catalyzing the reaction between the epoxide groups of NPGDGE and the hydroxyl groups of cellulose. Possible reaction routes were discussed. Scanning electron microscopy (SEM) images showed that while the MgBr 2 -catalyzed reaction resulted in self-polymerization of NPGDGE, the NaOH-catalyzed reaction did not. Fourier transform infrared spectroscopy (FTIR) showed that at high NaOH concentration cellulose restructures from allomorph I to II. NMR studies verified the incorporation of NPGDGE into cotton fabrics with a clear NMR signal, and confirmed that at higher NaOH concentration the efficiency of grafting of NPGDGE was increased. This demonstrates that use of solid state NMR directly on woven fabric samples can simultaneously characterize chemical modification and crystalline polymorph of cotton. No loss of tensile strength was observed for cotton fabrics modified with NPGDGE. Copyright © 2017 Elsevier Ltd. All rights reserved.
Xu, Tengfei; Paik, Inyup; Hanke, Sebastian; Keim, Sarah; Hermann, Helen-Maria; Wolf, Luise; Becker, Claude
2017-01-01
Across the plant kingdom, phytochrome (PHY) photoreceptors play an important role during adaptive and developmental responses to light. In Arabidopsis thaliana, light-activated PHYs accumulate in the nucleus, where they regulate downstream signaling components, such as phytochrome interacting factors (PIFs). PIFs are transcription factors that act as repressors of photomorphogenesis; their inhibition by PHYs leads to substantial changes in gene expression. The nuclear function of PHYs, however, has so far been investigated in only a few non-seed plants. Here, we identified putative target genes of PHY signaling in the moss Physcomitrella patens and found light-regulated genes that are putative orthologs of PIF-controlled genes in Arabidopsis. Phylogenetic analyses revealed that an ancestral PIF-like gene was already present in streptophyte algae, i.e., before the water-to-land transition of plants. The PIF homologs in the genome of P. patens resemble Arabidopsis PIFs in their protein domain structure, molecular properties, and physiological effects, albeit with notable differences in the motif-dependent PHY interaction. Our results suggest that P. patens PIFs are involved in PHY signaling. The PHY-PIF signaling node that relays light signals to target genes has been largely conserved during land plant evolution, with evidence of lineage-specific diversification. PMID:28123107
Midgley, David J; Sutcliffe, Brodie; Greenfield, Paul; Tran-Dinh, Nai
2018-05-01
This study describes a novel ericoid mycorrhizal fungus (ErMF), Gamarada debralockiae Midgley and Tran-Dinh gen. nov. sp. nov. Additionally, catabolism was explored from a genomic perspective. The nuclear and mitochondrial genomes of G. debralockiae were sequenced. Morphological characteristics were assessed on various media. Catabolic genes of G. debralockiae were explored using SignalP and dbCAN. Phylogenetic comparisons were undertaken using Phylogeny.fr. The 58.5-Mbp draft genome of G. debralockiae contained 17,075 putative genes. The complete mitochondrial genome was 28,168 bp in length. In culture, G. debralockiae produces slow-growing non-sporulating colonies. Gamarada debralockiae has many putative secreted catabolic enzymes. Phylogeny indicated G. debralockiae was distinct from known ascomycetous ErMF: Pezoloma ericae, Meliniomyces spp., Oidiodendron spp., and Cairneyella variabilis. It is closely related to many undescribed plant root-associated fungi and its nearest described relative is Hyphodiscus brevicollaris. Gamarada debralockiae has been recovered from virtually all Australian ericoid mycorrhizal studies and biogeographic data suggests the taxon is widespread in Australia. Gamarada debralockiae has similar catabolic potential to C. variabilis and co-occurs with C. variabilis at Australian sites. Plants that host multiple ErMF may benefit from subtle differences in catabolism that improve access to nitrogen and phosphorus from within recalcitrant organic matter.
Bryan, Anthony C; Zhang, Jin; Guo, Jianjun; Ranjan, Priya; Singan, Vasanth; Barry, Kerrie; Schmutz, Jeremy; Weighill, Deborah; Jacobson, Daniel; Jawdy, Sara; Tuskan, Gerald A; Chen, Jin-Gui; Muchero, Wellington
2018-06-08
Polyglutamine (polyQ) stretches have been reported to occur in proteins across many organisms including animals, fungi and plants. Expansion of these repeats has attracted much attention due their associations with numerous human diseases including Huntington's and other neurological maladies. This suggests that the relative length of polyQ stretches is an important modulator of their function. Here, we report the identification of a Populus C-terminus binding protein (CtBP) ANGUSTIFOLIA ( PtAN1 ) which contains a polyQ stretch whose functional relevance had not been established. Analysis of 917 resequenced Populus trichocarpa genotypes revealed three allelic variants at this locus encoding 11-, 13- and 15-glutamine residues. Transient expression assays using Populus leaf mesophyll protoplasts revealed that the 11Q variant exhibited strong nuclear localization whereas the 15Q variant was only found in the cytosol, with the 13Q variant exhibiting localization in both subcellular compartments. We assessed functional implications by evaluating expression changes of putative PtAN1 targets in response to overexpression of the three allelic variants and observed allele-specific differences in expression levels of putative targets. Our results provide evidence that variation in polyQ length modulates PtAN1 function by altering subcellular localization. Copyright © 2018, G3: Genes, Genomes, Genetics.
Kumar, Hitesh; Kumar, Sanjay
2013-09-15
The leaves of stevia [Stevia rebaudiana (Bertoni)] are a rich source of steviol glycosides that are used as non-calorific sweetener in many countries around the world. Steviol moiety of steviol glycosides is synthesized via plastidial 2C-methyl-D-erythritol 4-phosphate pathway, where (E)-4-hydroxy-3-methylbut-2-enyl diphosphate reductase (HDR) is the key enzyme. HDR catalyzes the simultaneous conversion of (E)-4-hydroxy-3-methylbut-2-enyl diphosphate into five carbon isoprenoid units, isopentenyl diphosphate and dimethylallyl diphosphate. Stevia HDR (SrHDR) successfully rescued HDR lethal mutant strain MG1655 ara<>ispH upon genetic complementation, suggesting SrHDR to encode a functional protein. The gene exhibited diurnal variation in expression. To identify the possible regulatory elements, upstream region of the gene was cloned and putative cis-acting elements were detected by in silico analysis. Electrophoretic mobility shift assay, using a putative light responsive element GATA showed the binding of nuclear proteins (NP) isolated from leaves during light period of the day, but not with the NP from leaves during the dark period. Data suggested the involvement of GATA box in light mediated gene regulation of SrHDR in stevia. Copyright © 2013 Elsevier B.V. All rights reserved.
Genetic modifiers of abnormal organelle biogenesis in a Drosophila model of BLOC-1 deficiency
Cheli, Verónica T.; Daniels, Richard W.; Godoy, Ruth; Hoyle, Diego J.; Kandachar, Vasundhara; Starcevic, Marta; Martinez-Agosto, Julian A.; Poole, Stephen; DiAntonio, Aaron; Lloyd, Vett K.; Chang, Henry C.; Krantz, David E.; Dell'Angelica, Esteban C.
2010-01-01
Biogenesis of lysosome-related organelles complex 1 (BLOC-1) is a protein complex formed by the products of eight distinct genes. Loss-of-function mutations in two of these genes, DTNBP1 and BLOC1S3, cause Hermansky–Pudlak syndrome, a human disorder characterized by defective biogenesis of lysosome-related organelles. In addition, haplotype variants within the same two genes have been postulated to increase the risk of developing schizophrenia. However, the molecular function of BLOC-1 remains unknown. Here, we have generated a fly model of BLOC-1 deficiency. Mutant flies lacking the conserved Blos1 subunit displayed eye pigmentation defects due to abnormal pigment granules, which are lysosome-related organelles, as well as abnormal glutamatergic transmission and behavior. Epistatic analyses revealed that BLOC-1 function in pigment granule biogenesis requires the activities of BLOC-2 and a putative Rab guanine-nucleotide-exchange factor named Claret. The eye pigmentation phenotype was modified by misexpression of proteins involved in intracellular protein trafficking; in particular, the phenotype was partially ameliorated by Rab11 and strongly enhanced by the clathrin-disassembly factor, Auxilin. These observations validate Drosophila melanogaster as a powerful model for the study of BLOC-1 function and its interactions with modifier genes. PMID:20015953
Zhang, Li; Liang, Shuli; Zhou, Xinying; Jin, Zi; Jiang, Fengchun; Han, Shuangyan; Zheng, Suiping
2013-01-01
Glycosylphosphatidylinositol (GPI)-anchored glycoproteins have various intrinsic functions in yeasts and different uses in vitro. In the present study, the genome of Pichia pastoris GS115 was screened for potential GPI-modified cell wall proteins. Fifty putative GPI-anchored proteins were selected on the basis of (i) the presence of a C-terminal GPI attachment signal sequence, (ii) the presence of an N-terminal signal sequence for secretion, and (iii) the absence of transmembrane domains in mature protein. The predicted GPI-anchored proteins were fused to an alpha-factor secretion signal as a substitute for their own N-terminal signal peptides and tagged with the chimeric reporters FLAG tag and mature Candida antarctica lipase B (CALB). The expression of fusion proteins on the cell surface of P. pastoris GS115 was determined by whole-cell flow cytometry and immunoblotting analysis of the cell wall extracts obtained by β-1,3-glucanase digestion. CALB displayed on the cell surface of P. pastoris GS115 with the predicted GPI-anchored proteins was examined on the basis of potential hydrolysis of p-nitrophenyl butyrate. Finally, 13 proteins were confirmed to be GPI-modified cell wall proteins in P. pastoris GS115, which can be used to display heterologous proteins on the yeast cell surface. PMID:23835174
Discovery of nuclear tracks in interplanetary dust
NASA Technical Reports Server (NTRS)
Bradley, J. P.; Brownlee, D. E.; Fraundorf, P.
1984-01-01
Nuclear tracks have been identified in interplanetary dust particles (IDP's) collected from the stratosphere. The presence of tracks unambiguously confirms the extraterrestrial nature of IDP's, and the high track densities (10 to the 10th to 10 to the 11th per square centimeter) suggest an exposure age of approximately 10,000 years within the inner solar system. Tracks also provide an upper temperature limit for the heating of IDP's during atmospheric entry, thereby making it possible to distinguish between pristine and thermally modified micrometeorites.
Fractal Approach to the Regional Seismic Event Discrimination Problem
2000-01-01
some H > 0 and this formula might be modified as X(t) = r-HX(rt),t E R (2) where H is the Hurst exponent . Traditionally it is estimated by the...2 3 IogT Figure 2. Hurst exponent H curves for different seismic events: Pakl - nuclear explosion 30.05.98 (Pakistan), ind - nuclear explosion...seismic discrimination. Our findings are summarized in the conclusion section. 261 2 Hurst’s exponents of seismograms We started from the study of self
Phospholipid Regulation of the Nuclear Receptor Superfamily
Crowder, Mark K.; Seacrist, Corey D.; Blind, Raymond D.
2016-01-01
Nuclear receptors are ligand-activated transcription factors whose diverse biological functions are classically regulated by cholesterol-based small molecules. Over the past few decades, a growing body of evidence has demonstrated that phospholipids and other similar amphipathic molecules can also specifically bind and functionally regulate the activity of certain nuclear receptors, suggesting a critical role for these non-cholesterol-based molecules in transcriptional regulation. Phosphatidylcholines, phosphoinositides and sphingolipids are a few of the many phospholipid like molecules shown to quite specifically regulate nuclear receptors in mouse models, cell lines and in vitro. More recent evidence has also shown that certain nuclear receptors can “present” a bound phospholipid headgroup to key lipid signaling enzymes, which can then modify the phospholipid headgroup with very unique kinetic properties. Here, we review the broad array of phospholipid / nuclear receptor interactions, from the perspective of the chemical nature of the phospholipid, and the cellular abundance of the phospholipid. We also view the data in the light of well established paradigms for phospholipid mediated transcriptional regulation, as well as newer models of how phospholipids might effect transcription in the acute regulation of complex nuclear signaling pathways. Thus, this review provides novel insight into the new, non-membrane associated roles nuclear phospholipids play in regulating complex nuclear events, centered on the nuclear receptor superfamily of transcription factors. PMID:27838257
Hyperforin modifies neuronal membrane properties in vivo.
Eckert, Gunter P; Keller, Jan-Henning; Jourdan, Claudia; Karas, Michael; Volmer, Dietrich A; Schubert-Zsilavecz, Manfred; Müller, Walter E
2004-09-02
Hyperforin, the major active constituent of St. John Wort (SJW) extract, affects several neurotransmitter systems in the brain putatively by modulation of the physical state of neuronal membranes. Accordingly, we tested the effects of SJW extract and of hyperforin on the properties of murine brain membrane fluidity. Oral administration of SJW extract and of hyperforin sodium salt results in significant hyperforin brain levels. Treatment of mice with hyperforin leads to decreased annular- and bulk fluidity and increased acyl-chain flexibility of brain membranes. All hyperforin related changes of membrane properties were significantly correlated with the corresponding hyperforin brain levels. Our data emphasises a membrane interaction of hyperforin that possibly contributes to its pharmacological effects.
Dinnsen, Daniel A.; Dow, Michael C.; Gierut, Judith A.; Morrisette, Michele L.; Green, Christopher R.
2013-01-01
This paper examines a range of predicted versus attested error patterns involving coronal fricatives (e.g. [s, z, θ, ð]) as targets and repairs in the early sound systems of monolingual English-acquiring children. Typological results are reported from a cross-sectional study of 234 children with phonological delays (ages 3 years; 0 months to 7;9). Our analyses revealed different instantiations of a putative developmental conspiracy within and across children. Supplemental longitudinal evidence is also presented that replicates the cross-sectional results, offering further insight into the life-cycle of the conspiracy. Several of the observed typological anomalies are argued to follow from a modified version of Optimality Theory with Candidate Chains (McCarthy, 2007). PMID:24790247
BPF-1, a pathogen-induced DNA-binding protein involved in the plant defense response.
da Costa e Silva, O; Klein, L; Schmelzer, E; Trezzini, G F; Hahlbrock, K
1993-07-01
The mechanisms by which plants restrict the growth of pathogens include transient activation of numerous defense-related genes. Box P is a putative cis-acting element of a distinct group of such genes, including those encoding the enzyme phenylalanine ammonialyase (PAL). A DNA-binding activity to Box P was identified in nuclear extracts from cultured parsley cells and a cDNA encoding the protein BPF-1 (Box P-binding Factor) partially characterized. BPF-1 binds to this element with specificity similar to that of the binding activity in nuclear extracts. BPF-1 mRNA accumulates rapidly in elicitor-treated parsley cells and around fungal infection sites on parsley leaves. This accumulation is, at least partly, due to a rapid and transient increase in the transcription rate of BPF-1. Moreover, tight correlation between the relative amounts of BPF-1 and PAL mRNAs was observed in different organs of a parsley plant. These results are consistent with the hypothesis that BPF-1 is involved in disease resistance by modulating plant defense gene expression.
Sturm, Sonja; Seger, Christoph; Godejohann, Markus; Spraul, Manfred; Stuppner, Hermann
2007-09-07
Identification of putative biomarker molecules within the genus Corydalis (Papaveraceae) was pursued by combining conventional off-line sample enrichment with high-performance liquid chromatography-solid phase extraction-nuclear magnetic resonance (HPLC-SPE-NMR) based structure elucidation. Off-line reversed phase solid phase extraction (SPE) was used to enrich the desired analytes from a methanolic extract (93 mg dry weight) of a miniscule single tuber (233 mg dry weight) of C. solida. An aliquot of the SPE fraction (2.1 mg) was subjected to separation in the HPLC-SPE-NMR hyphenation. Chromatographic peaks bearing the metabolites under investigation were trapped in the SPE device in a single experiment and transferred to a 600 MHz NMR spectrometer equipped with a 30 microl cryofit insert fed into a 3 mm cryoprobe. Recorded homo- and heteronuclear 1D and 2D NMR data allowed the identification of the three analytes under investigation as protopine, allocryptopine, and N-methyl-laudanidinium acetate. The latter is a rare alkaloid, which has been isolated only once before.
Kuchta, Shawn R.; Brown, Ashley D.; Converse, Paul E.; Highton, Richard
2016-01-01
Species are a fundamental unit of biodiversity, yet can be challenging to delimit objectively. This is particularly true of species complexes characterized by high levels of population genetic structure, hybridization between genetic groups, isolation by distance, and limited phenotypic variation. Previous work on the Cumberland Plateau Salamander, Plethodon kentucki, suggested that it might constitute a species complex despite occupying a relatively small geographic range. To examine this hypothesis, we sampled 135 individuals from 43 populations, and used four mitochondrial loci and five nuclear loci (5693 base pairs) to quantify phylogeographic structure and probe for cryptic species diversity. Rates of evolution for each locus were inferred using the multidistribute package, and time calibrated gene trees and species trees were inferred using BEAST 2 and *BEAST 2, respectively. Because the parameter space relevant for species delimitation is large and complex, and all methods make simplifying assumptions that may lead them to fail, we conducted an array of analyses. Our assumption was that strongly supported species would be congruent across methods. Putative species were first delimited using a Bayesian implementation of the GMYC model (bGMYC), Geneland, and Brownie. We then validated these species using the genealogical sorting index and BPP. We found substantial phylogeographic diversity using mtDNA, including four divergent clades and an inferred common ancestor at 14.9 myr (95% HPD: 10.8–19.7 myr). By contrast, this diversity was not corroborated by nuclear sequence data, which exhibited low levels of variation and weak phylogeographic structure. Species trees estimated a far younger root than did the mtDNA data, closer to 1.0 myr old. Mutually exclusive putative species were identified by the different approaches. Possible causes of data set discordance, and the problem of species delimitation in complexes with high levels of population structure and introgressive hybridization, are discussed. PMID:26974148
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Xinxin; Zhang, Min; Takano, Tetsuo
Highlights: {yields} The AtCCX5 protein coding a putative cation calcium exchanger was characterized. {yields} AtCCX5 expressed in yeast was localized in the plasma membrane and nuclear periphery. {yields} AtCCX5 protein did not show the same transport properties as the CAXs. {yields} AtCCX5 protein involves in mediating high-affinity K{sup +} uptake in yeast. {yields} AtCCX5 protein also involves in Na{sup +} transport in yeast. -- Abstract: The gene for a putative cation calcium exchanger (CCX) from Arabidopsis thaliana, AtCCX5, was cloned and its function was analyzed in yeast. Green fluorescent protein-tagged AtCCX5 expressed in yeast was localized in the plasma membranemore » and nuclear periphery. The yeast transformants expressing AtCCX5 were created and their growth in the presence of various cations (K{sup +}, Na{sup +}, Ca{sup 2+}, Mg{sup 2+}, Fe{sup 2+}, Cu{sup 2+}, Co{sup 2+}, Cd{sup 2+}, Mn{sup 2+}, Ba{sup 2+}, Ni{sup 2+}, Zn{sup 2+}, and Li{sup +}) were analyzed. AtCCX5 expression was found to affect the response to K{sup +} and Na{sup +} in yeast. The AtCCX5 transformant also showed a little better growth to Zn{sup 2+}. The yeast mutant 9.3 expressing AtCCX5 restored growth of the mutant on medium with low K{sup +} (0.5 mM), and also suppressed its Na{sup +} sensitivity. Ion uptake experiments showed that AtCCX5 mediated relatively high-affinity K{sup +} uptake and was also involved in Na{sup +} transport in yeast. Taken together, these findings suggest that the AtCCX5 is a novel transport protein involves in mediating high-affinity K{sup +} uptake and Na{sup +} transport in yeast.« less
Zhang, Kun; Li, Yu-Jiao; Guo, Yanyan; Zheng, Kai-Yin; Yang, Qi; Yang, Le; Wang, Xin-Shang; Song, Qian; Chen, Tao; Zhuo, Min; Zhao, Ming-Gao
2017-12-01
Fragile X syndrome is an inheritable form of intellectual disability caused by loss of fragile X mental retardation protein (FMRP, encoded by the FMR1 gene). Absence of FMRP caused overexpression of progranulin (PGRN, encoded by GRN), a putative tumour necrosis factor receptor ligand. In the present study, we found that progranulin mRNA and protein were upregulated in the medial prefrontal cortex of Fmr1 knock-out mice. In Fmr1 knock-out mice, elevated progranulin caused insufficient dendritic spine pruning and late-phase long-term potentiation in the medial prefrontal cortex of Fmr1 knock-out mice. Partial progranulin knock-down restored spine morphology and reversed behavioural deficits, including impaired fear memory, hyperactivity, and motor inflexibility in Fmr1 knock-out mice. Progranulin increased levels of phosphorylated glutamate ionotropic receptor GluA1 and nuclear factor kappa B in cultured wild-type neurons. Tumour necrosis factor receptor 2 antibody perfusion blocked the effects of progranulin on GluA1 phosphorylation; this result indicates that tumour necrosis factor receptor 2 is required for progranulin-mediated GluA1 phosphorylation and late-phase long-term potentiation expression. However, high basal level of progranulin in Fmr1 knock-out mice prevented further facilitation of synaptic plasticity by exogenous progranulin. Partial downregulation of progranulin or tumour necrosis factor receptor 2/nuclear factor kappa B signalling restored synaptic plasticity and memory deficits in Fmr1 knock-out mice. These findings suggest that elevated PGRN is linked to cognitive deficits of fragile X syndrome, and the progranulin/tumour necrosis factor receptor 2 signalling pathway may be a putative therapeutic target for improving cognitive deficits in fragile X syndrome. © The Author (2017). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
A study on the dependence of nuclear viscosity on temperature
NASA Astrophysics Data System (ADS)
Vardaci, E.; Di Nitto, A.; Nadtochy, P. N.; La Rana, G.; Cinausero, M.; Prete, G.; Gelli, N.; Ashaduzzaman, M.; Davide, F.; Pulcini, A.; Quero, D.; Kozulin, E. M.; Knyazheva, G. N.; Itkis, I. M.
2018-05-01
Nuclear viscosity is an irreplaceable ingredient of nuclear fission collective dynamical models. It drives the exchange of energy between the collective variables and the thermal bath of single particle degrees of freedom. Its dependence on the shape and temperature is a matter of controversy. By using systems of intermediate fissility we have demonstrated in a recent study that the viscosity parameters is larger for compact shapes, and decreases for larger deformations of the fissioning system, at variance with the conclusions of the statistical model modified to include empirically viscosity and time scales. In this contribution we propose an experimental scenario to highlight the possible dependence of the viscosity from the temperature.
Reininghaus, Ulrich; Depp, Colin A.; Myin-Germeys, Inez
2016-01-01
Integrated models of psychotic disorders have posited a number of putative psychological mechanisms that may contribute to the development of psychotic symptoms, but it is only recently that a modest amount of experience sampling research has provided evidence on their role in daily life, outside the research laboratory. A number of methodological challenges remain in evaluating specificity of potential causal links between a given psychological mechanism and psychosis outcomes in a systematic fashion, capitalizing on longitudinal data to investigate temporal ordering. In this article, we argue for testing ecological interventionist causal models that draw on real world and real-time delivered, ecological momentary interventions for generating evidence on several causal criteria (association, time order, and direction/sole plausibility) under real-world conditions, while maximizing generalizability to social contexts and experiences in heterogeneous populations. Specifically, this approach tests whether ecological momentary interventions can (1) modify a putative mechanism and (2) produce changes in the mechanism that lead to sustainable changes in intended psychosis outcomes in individuals’ daily lives. Future research using this approach will provide translational evidence on the active ingredients of mobile health and in-person interventions that promote sustained effectiveness of ecological momentary interventions and, thereby, contribute to ongoing efforts that seek to enhance effectiveness of psychological interventions under real-world conditions. PMID:26707864
Mathupala, S P; Lowe, S E; Podkovyrov, S M; Zeikus, J G
1993-08-05
The complete nucleotide sequence of the gene encoding the dual active amylopullulanase of Thermoanaerobacter ethanolicus 39E (formerly Clostridium thermohydrosulfuricum) was determined. The structural gene (apu) contained a single open reading frame 4443 base pairs in length, corresponding to 1481 amino acids, with an estimated molecular weight of 162,780. Analysis of the deduced sequence of apu with sequences of alpha-amylases and alpha-1,6 debranching enzymes enabled the identification of four conserved regions putatively involved in substrate binding and in catalysis. The conserved regions were localized within a 2.9-kilobase pair gene fragment, which encoded a M(r) 100,000 protein that maintained the dual activities and thermostability of the native enzyme. The catalytic residues of amylopullulanase were tentatively identified by using hydrophobic cluster analysis for comparison of amino acid sequences of amylopullulanase and other amylolytic enzymes. Asp597, Glu626, and Asp703 were individually modified to their respective amide form, or the alternate acid form, and in all cases both alpha-amylase and pullulanase activities were lost, suggesting the possible involvement of 3 residues in a catalytic triad, and the presence of a putative single catalytic site within the enzyme. These findings substantiate amylopullulanase as a new type of amylosaccharidase.
Protein and gene structure of a blue laccase from Pleurotus ostreatus1.
Giardina, P; Palmieri, G; Scaloni, A; Fontanella, B; Faraco, V; Cennamo, G; Sannia, G
1999-01-01
A new laccase isoenzyme (POXA1b, where POX is phenol oxidase), produced by Pleurotus ostreatus in cultures supplemented with copper sulphate, has been purified and fully characterized. The main characteristics of this protein (molecular mass in native and denaturing conditions, pI and catalytic properties) are almost identical to the previously studied laccase POXA1w. However, POXA1b contains four copper atoms per molecule instead of one copper, two zinc and one iron atom per molecule of POXA1w. Furthermore, POXA1b shows an unusually high stability at alkaline pH. The gene and cDNA coding for POXA1b have been cloned and sequenced. The gene coding sequence contains 1599 bp, interrupted by 15 introns. Comparison of the structure of the poxa1b gene with the two previously studied P. ostreatus laccase genes (pox1 and poxc) suggests that these genes belong to two different subfamilies. The amino acid sequence of POXA1b deduced from the cDNA sequence has been almost completely verified by means of matrix-assisted laser desorption ionization MS. It has been demonstrated that three out of six putative glycosylation sites are post-translationally modified and the structure of the bound glycosidic moieties has been determined, whereas two other putative glycosylation sites are unmodified. PMID:10417329
Li, J; Kolling, G L; Matthews, K R; Chikindas, M L
2003-01-01
To study whether the exposure to cold (4 degrees C) and carbon dioxide which results in the elongation of Listeria cells, induces a viable but nonculturable (VBNC) state. When cold and CO2 stressed L. monocytogenes were observed under a fluorescence microscope, using the LIVE/DEAD BacLight bacteria viability kit (Molecular Probes, Eugene, OR, USA), the healthy, mildly injured, and the putative VBNC cells accounted for 31.0% of the stressed cell population. By using the selective plate count, 31.4% of the same stressed cell population was found to be healthy and mildly injured (putative VBNC cells not included). If there were VBNC state cells present, we should have observed a significant difference between the above two numbers. In fact, there was no significant difference between the results obtained from those two methods. There were no VBNC state cells observed in the stressed cell population. We conclude that cold and CO2 do not induce L. monocytogenes to enter a VBNC state. Cold and modified atmospheres are widely used in fresh muscle food and fruit preservation. Whether they would induce L. monocytogenes into a VBNC state is of a great concern for microbial food safety.
Dejean, Laurent M.; Martinez-Caballero, Sonia; Guo, Liang; Hughes, Cynthia; Teijido, Oscar; Ducret, Thomas; Ichas, François; Korsmeyer, Stanley J.; Antonsson, Bruno; Jonas, Elizabeth A.; Kinnally, Kathleen W.
2005-01-01
Bcl-2 family proteins regulate apoptosis, in part, by controlling formation of the mitochondrial apoptosis-induced channel (MAC), which is a putative cytochrome c release channel induced early in the intrinsic apoptotic pathway. This channel activity was never observed in Bcl-2–overexpressing cells. Furthermore, MAC appears when Bax translocates to mitochondria and cytochrome c is released in cells dying by intrinsic apoptosis. Bax is a component of MAC of staurosporine-treated HeLa cells because MAC activity is immunodepleted by Bax antibodies. MAC is preferentially associated with oligomeric, not monomeric, Bax. The single channel behavior of recombinant oligomeric Bax and MAC is similar. Both channel activities are modified by cytochrome c, consistent with entrance of this protein into the pore. The mean conductance of patches of mitochondria isolated after green fluorescent protein-Bax translocation is significantly higher than those from untreated cells, consistent with onset of MAC activity. In contrast, the mean conductance of patches of mitochondria indicates MAC activity is present in apoptotic cells deficient in Bax but absent in apoptotic cells deficient in both Bax and Bak. These findings indicate Bax is a component of MAC in staurosporine-treated HeLa cells and suggest Bax and Bak are functionally redundant as components of MAC. PMID:15772159
Jacquelin, Lauriane; Desutter-Grandcolas, Laure; Chintauan-Marquier, Ioana; Boistel, Renaud; Zheng, Daran; Prokop, Jakub; Nel, André
2018-01-10
Being implied in flight, mimetism, communication, and protection, the insect wings were crucial organs for the mega diversification of this clade. Despite several attempts, the problem of wing evolution remains unresolved because the basal parts of the veins essential for vein identification are hidden in the basivenal sclerites. The homologies between wing characters thus cannot be accurately verified, while they are of primary importance to solve long-standing problems, such as the monophyly of the Palaeoptera, viz. Odonatoptera, Panephemeroptera, and Palaeozoic Palaeodictyopterida mainly known by their wings. Hitherto the tools to homologize venation were suffering several cases of exceptions, rendering them unreliable. Here we reconstruct the odonatopteran venation using fossils and a new 3D imaging tool, resulting congruent with the concept of Riek and Kukalová-Peck, with important novelties, viz. median anterior vein fused to radius and radius posterior nearly as convex as radius anterior (putative synapomorphies of Odonatoptera); subcostal anterior (ScA) fused to costal vein and most basal primary antenodal crossvein being a modified posterior branch of ScA (putative synapomorphies of Palaeoptera). These findings may reveal critical for future analyses of the relationships between fossil and extant Palaeoptera, helping to solve the evolutionary history of the insects as a whole.
Morra, Joshua T.; Glick, Stanley D.; Cheer, Joseph F.
2012-01-01
Patients suffering from amphetamine---induced psychosis display repetitive behaviors, partially alleviated by antipsychotics, which are reminiscent of rodent stereotypies. Due to recent evidence implicating endocannabinoid involvement in brain disorders, including psychosis, we studied the effects of endocannabinoid signaling on neuronal oscillations of rats exhibiting methamphetamine stereotypy. Neuronal network oscillations were recorded with multiple single electrode arrays aimed at the nucleus accumbens of freely moving rats. During the experiments, animals were dosed intravenously with the CB1 receptor antagonist rimonabant (0.3 mg/kg) or vehicle followed by an ascending dose regimen of methamphetamine (0.01, 0.1, 1, and 3 mg/kg; cumulative dosing). The effects of drug administration on stereotypy and local gamma oscillations were evaluated. Methamphetamine treatment significantly increased high frequency gamma oscillations (~ 80 Hz). Entrainment of a subpopulation of nucleus accumbens neurons to high frequency gamma was associated with stereotypy encoding in putative fast-spiking interneurons, but not in putative medium spiny neurons. The observed ability of methamphetamine to induce both stereotypy and high frequency gamma power was potently disrupted following CB1 receptor blockade. The present data suggest that CB1 receptor-dependent mechanisms are recruited by methamphetamine to modify striatal interneuron oscillations that accompany changes in psychomotor state, further supporting the link between endocannabinoids and schizophrenia spectrum disorders. PMID:22609048
Supernovae neutrino pasta interaction
NASA Astrophysics Data System (ADS)
Lin, Zidu; Horowitz, Charles; Caplan, Matthew; Berry, Donald; Roberts, Luke
2017-01-01
In core-collapse supernovae, the neutron rich matter is believed to have complex structures, such as spherical, slablike, and rodlike shapes. They are collectively called ``nuclear pasta''. Supernovae neutrinos may scatter coherently on the ``nuclear pasta'' since the wavelength of the supernovae neutrinos are comparable to the nuclear pasta scale. Consequently, the neutrino pasta scattering is important to understand the neutrino opacity in the supernovae. In this work we simulated the ``nuclear pasta'' at different temperatures and densities using our semi-classical molecular dynamics and calculated the corresponding static structure factor that describes ν-pasta scattering. We found the neutrino opacities are greatly modified when the ``pasta'' exist and may have influence on the supernovae neutrino flux and average energy. Our neutrino-pasta scattering effect can finally be involved in the current supernovae simulations and we present preliminary proto neutron star cooling simulations including our pasta opacities.
Analysis of URI nuclear interaction with RPB5 and components of the R2TP/prefoldin-like complex.
Mita, Paolo; Savas, Jeffrey N; Ha, Susan; Djouder, Nabil; Yates, John R; Logan, Susan K
2013-01-01
Unconventional prefoldin RPB5 Interactor (URI) was identified as a transcriptional repressor that binds RNA polymerase II (pol II) through interaction with the RPB5/POLR2E subunit. Despite the fact that many other proteins involved in transcription regulation have been shown to interact with URI, its nuclear function still remains elusive. Previous mass spectrometry analyses reported that URI is part of a novel protein complex called R2TP/prefoldin-like complex responsible for the cytoplasmic assembly of RNA polymerase II. We performed a mass spectrometry (MS)-based proteomic analysis to identify nuclear proteins interacting with URI in prostate cells. We identified all the components of the R2TP/prefoldin-like complex as nuclear URI interactors and we showed that URI binds and regulates RPB5 protein stability and transcription. Moreover, we validated the interaction of URI to the P53 and DNA damage-Regulated Gene 1 (PDRG1) and show that PDRG1 protein is also stabilized by URI binding. We present data demonstrating that URI nuclear/cytoplasmic shuttling is affected by compounds that stall pol II on the DNA (α-amanitin and actinomycin-D) and by leptomycin B, an inhibitor of the CRM1 exportin that mediates the nuclear export of pol II subunits. These data suggest that URI, and probably the entire R2TP/prefoldin-like complex is exported from the nucleus through CRM1. Finally we identified putative URI sites of phosphorylation and acetylation and confirmed URI sites of post-transcriptional modification identified in previous large-scale analyses the importance of which is largely unknown. However URI post-transcriptional modification was shown to be essential for URI function and therefore characterization of novel sites of URI modification will be important to the understanding of URI function.
Analysis of URI Nuclear Interaction with RPB5 and Components of the R2TP/Prefoldin-Like Complex
Mita, Paolo; Savas, Jeffrey N.; Ha, Susan; Djouder, Nabil; Yates, John R.; Logan, Susan K.
2013-01-01
Unconventional prefoldin RPB5 Interactor (URI) was identified as a transcriptional repressor that binds RNA polymerase II (pol II) through interaction with the RPB5/POLR2E subunit. Despite the fact that many other proteins involved in transcription regulation have been shown to interact with URI, its nuclear function still remains elusive. Previous mass spectrometry analyses reported that URI is part of a novel protein complex called R2TP/prefoldin-like complex responsible for the cytoplasmic assembly of RNA polymerase II. We performed a mass spectrometry (MS)-based proteomic analysis to identify nuclear proteins interacting with URI in prostate cells. We identified all the components of the R2TP/prefoldin-like complex as nuclear URI interactors and we showed that URI binds and regulates RPB5 protein stability and transcription. Moreover, we validated the interaction of URI to the P53 and DNA damage-Regulated Gene 1 (PDRG1) and show that PDRG1 protein is also stabilized by URI binding. We present data demonstrating that URI nuclear/cytoplasmic shuttling is affected by compounds that stall pol II on the DNA (α-amanitin and actinomycin-D) and by leptomycin B, an inhibitor of the CRM1 exportin that mediates the nuclear export of pol II subunits. These data suggest that URI, and probably the entire R2TP/prefoldin-like complex is exported from the nucleus through CRM1. Finally we identified putative URI sites of phosphorylation and acetylation and confirmed URI sites of post-transcriptional modification identified in previous large-scale analyses the importance of which is largely unknown. However URI post-transcriptional modification was shown to be essential for URI function and therefore characterization of novel sites of URI modification will be important to the understanding of URI function. PMID:23667685
Grandi, Paola; Dang, Tam; Pané, Nelly; Shevchenko, Andrej; Mann, Matthias; Forbes, Douglass; Hurt, Ed
1997-01-01
Yeast and vertebrate nuclear pores display significant morphological similarity by electron microscopy, but sequence similarity between the respective proteins has been more difficult to observe. Herein we have identified a vertebrate nucleoporin, Nup93, in both human and Xenopus that has proved to be an evolutionarily related homologue of the yeast nucleoporin Nic96p. Polyclonal antiserum to human Nup93 detects corresponding proteins in human, rat, and Xenopus cells. Immunofluorescence and immunoelectron microscopy localize vertebrate Nup93 at the nuclear basket and at or near the nuclear entry to the gated channel of the pore. Immunoprecipitation from both mammalian and Xenopus cell extracts indicates that a small fraction of Nup93 physically interacts with the nucleoporin p62, just as yeast Nic96p interacts with the yeast p62 homologue. However, a large fraction of vertebrate Nup93 is extracted from pores and is also present in Xenopus egg extracts in complex with a newly discovered 205-kDa protein. Mass spectrometric sequencing of the human 205-kDa protein reveals that this protein is encoded by an open reading frame, KIAAO225, present in the human database. The putative human nucleoporin of 205 kDa has related sequence homologues in Caenorhabditis elegans and Saccharomyces cerevisiae. To analyze the role of the Nup93 complex in the pore, nuclei were assembled that lack the Nup93 complex after immunodepletion of a Xenopus nuclear reconstitution extract. The Nup93-complex–depleted nuclei are clearly defective for correct nuclear pore assembly. From these experiments, we conclude that the vertebrate and yeast pore have significant homology in their functionally important cores and that, with the identification of Nup93 and the 205-kDa protein, we have extended the knowledge of the nearest-neighbor interactions of this core in both yeast and vertebrates. PMID:9348540
Cheng, Yu Ti; Germain, Hugo; Wiermer, Marcel; Bi, Dongling; Xu, Fang; García, Ana V; Wirthmueller, Lennart; Després, Charles; Parker, Jane E; Zhang, Yuelin; Li, Xin
2009-08-01
Plant immune responses depend on dynamic signaling events across the nuclear envelope through nuclear pores. Nuclear accumulation of certain resistance (R) proteins and downstream signal transducers are critical for their functions, but it is not understood how these processes are controlled. Here, we report the identification, cloning, and analysis of Arabidopsis thaliana modifier of snc1,7 (mos7-1), a partial loss-of-function mutation that suppresses immune responses conditioned by the autoactivated R protein snc1 (for suppressor of npr1-1, constitutive 1). mos7-1 single mutant plants exhibit defects in basal and R protein-mediated immunity and in systemic acquired resistance but do not display obvious pleiotropic defects in development, salt tolerance, or plant hormone responses. MOS7 is homologous to human and Drosophila melanogaster nucleoporin Nup88 and resides at the nuclear envelope. In animals, Nup88 attenuates nuclear export of activated NF-kappaB transcription factors, resulting in nuclear accumulation of NF-kappaB. Our analysis shows that nuclear accumulation of snc1 and the defense signaling components Enhanced Disease Susceptibility 1 and Nonexpresser of PR genes 1 is significantly reduced in mos7-1 plants, while nuclear retention of other tested proteins is unaffected. The data suggest that specifically modulating the nuclear concentrations of certain defense proteins regulates defense outputs.
Richter, Grace M.; Torres, Mina; Choudhury, Farzana; Azen, Stanley P.; Varma, Rohit
2012-01-01
Purpose To identify socio-demographic and biological risk factors associated with having cortical, nuclear, posterior sub-capsular (PSC), and mixed lens opacities. Design Population-based, cross-sectional study Participants Five thousand nine hundred forty-five Latinos 40 years and older from 6 census tracts in Los Angeles, California. Methods Participants underwent an interview and detailed eye examination, including best-corrected visual acuity and slit-lamp assessment of lens opacities using the Lens Opacities Classification System II. Univariate and stepwise logistic regression analyses were used to identify independent risk factors associated with each type of lens opacity. Main Outcome Measures Odds ratios for socio-demographic and biological risk factors associated with cortical only, nuclear only, PSC only, and mixed lens opacities. Results Of the 5945 participants with gradable lenses, 468 had cortical only lens opacities, 217 had nuclear only lens opacities, 27 had PSC only opacities, and 364 had mixed lens opacities. Older age, higher hemoglobin A1c, and history of diabetes mellitus were independent risk factors for cortical only lens opacities. Older age, smoking, and myopic refractive error were independent risk factors for nuclear only lens opacities. Higher systolic blood pressure and history of diabetes were independent risk factors for posterior sub-capsular lens opacities. Older age, myopic refractive error, history of diabetes, higher systolic blood pressure, female gender, and presence of large drusen were independent risk factors for mixed lens opacities. Conclusions The modifiable and non-modifiable risk factors identified in this study provide insight into the mechanisms related to the development of lens opacification. Improved glycemic control, smoking cessation and prevention, and blood pressure control may help to reduce the risk of having lens opacities and their associated vision loss. PMID:22197433
Mukherjee, Ananda; Patterson, Amanda L; George, Jitu W; Carpenter, Tyler J; Madaj, Zachary B; Hostetter, Galen; Risinger, John I; Teixeira, Jose M
2018-06-13
Endometrial adenocarcinoma (EndoCA) is the most common gynecological cancer type in the US, and its incidence is increasing. The majority of patients are disease-free after surgical resection of stage I tumors, which is often followed by radiation therapy, but most patients with advanced disease recur and have a poor prognosis, largely because the tumors become refractory to cytotoxic chemotherapies. PTEN, a commonly mutated tumor suppressor in EndoCAs, is well known for its ability to inhibit the AKT/mTOR signaling pathway. Nuclear functions for PTEN have been proposed as well, but whether those affect EndoCA development, progression, or outcomes is not well understood. Using immunohistochemistry, nuclear PTEN expression was observed in approximately half of EndoCA patient tumors, independent of grade and cytoplasmic PTEN expression. Higher levels of the DNA damage response (DDR) marker, yH2AX, were observed by immunohistochemistry and immunofluorescence in human EndoCA tumor sections that were PTEN-negative, in murine EndoCA tissues that were genetically modified to be PTEN-null, and in Ishikawa EndoCA cells, which do not express endogenous PTEN. Over-expression of exogenous PTEN-WT or PTEN-NLS, a modified PTEN with an added nuclear localization signal, significantly improved both DDR and G2/M transition in Ishikawa cells treated with a DNA damaging agent. Whereas PARP inhibition with Olaparib was not as effective in Ishikawa cells expressing native or PTEN-NLS, inhibition with Talazoparib was not affected by PTEN overexpression. These results suggest that nuclear PTEN subcellular localization in human EndoCA could be diagnostic when considering DDR therapeutic intervention. Copyright ©2018, American Association for Cancer Research.
Whole blood genome-wide expression profiling and network analysis suggest MELAS master regulators.
Mende, Susanne; Royer, Loic; Herr, Alexander; Schmiedel, Janet; Deschauer, Marcus; Klopstock, Thomas; Kostic, Vladimir S; Schroeder, Michael; Reichmann, Heinz; Storch, Alexander
2011-07-01
The heteroplasmic mitochondrial DNA (mtDNA) mutation A3243G causes the mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome as one of the most frequent mitochondrial diseases. The process of reconfiguration of nuclear gene expression profile to accommodate cellular processes to the functional status of mitochondria might be a key to MELAS disease manifestation and could contribute to its diverse phenotypic presentation. To determine master regulatory protein networks and disease-modifying genes in MELAS syndrome. Analyses of whole blood transcriptomes from 10 MELAS patients using a novel strategy by combining classic Affymetrix oligonucleotide microarray profiling with regulatory and protein interaction network analyses. Hierarchical cluster analysis elucidated that the relative abundance of mutant mtDNA molecules is decisive for the nuclear gene expression response. Further analyses confirmed not only transcription factors already known to be involved in mitochondrial diseases (such as TFAM), but also detected the hypoxia-inducible factor 1 complex, nuclear factor Y and cAMP responsive element-binding protein-related transcription factors as novel master regulators for reconfiguration of nuclear gene expression in response to the MELAS mutation. Correlation analyses of gene alterations and clinico-genetic data detected significant correlations between A3243G-induced nuclear gene expression changes and mutant mtDNA load as well as disease characteristics. These potential disease-modifying genes influencing the expression of the MELAS phenotype are mainly related to clusters primarily unrelated to cellular energy metabolism, but important for nucleic acid and protein metabolism, and signal transduction. Our data thus provide a framework to search for new pathogenetic concepts and potential therapeutic approaches to treat the MELAS syndrome.
Metz-Flamant, C; Samson, E; Caër-Lorho, S; Acker, A; Laurier, D
2012-11-01
Leukemia is one of the earliest cancer effects observed after acute exposure to relatively high doses of ionizing radiation. Leukemia mortality after external exposure at low doses and low-dose rates has been investigated at the French Atomic Energy Commission (CEA) and Nuclear Fuel Company (AREVA NC) after an additional follow-up of 10 years. The cohort included radiation-monitored workers employed for at least one year during 1950-1994 at CEA or AREVA NC and followed during 1968-2004. Association between external exposure and leukemia mortality was estimated with excess relative risk (ERR) models and time-dependent modifying factors were investigated with time windows. The cohort included 36,769 workers, followed for an average of 28 years, among whom 73 leukemia deaths occurred. Among the workers with a positive recorded dose, the mean cumulative external dose was 21.7 mSv. Results under a 2-year lag assumption suggested that the risk of leukemia (except chronic lymphatic leukemia) increased significantly by 8% per 10 mSv. The magnitude of the association for myeloid leukemia was larger. The higher ERR/Sv for doses received 2-14 years earlier suggest that time since exposure modifies the effect. The ERR/Sv also appeared higher for doses received at exposure rates ≥20 mSv per year. These results are consistent with those found in other studies of nuclear workers. However, confidence intervals are still wide. Further analyses should be conducted in pooled cohorts of nuclear workers.
Fluoro-alcohol phase modifiers and process for cesium solvent extraction
Bonnesen, Peter V.; Moyer, Bruce A.; Sachleben, Richard A.
2003-05-20
The invention relates to a class of phenoxy fluoro-alcohols, their preparation, and their use as phase modifiers and solvating agents in a solvent composition for the extraction of cesium from alkaline solutions. These phenoxy fluoro-alcohols comply with the formula: ##STR1## in which n=2 to 4; X represents a hydrogen or a fluorine atom, and R.sup.2 -R.sup.6 are hydrogen or alkyl substituents. These phenoxy fluoro-alcohol phase modifiers are a necessary component to a robust solvent composition and process useful for the removal of radioactive cesium from alkaline nuclear waste streams. The fluoro-alcohols can also be used in solvents designed to extract other cesium from acidic or neutral solutions.
A Study of Biomolecules as Growth Modifiers of Calcium Oxalate Crystals
NASA Astrophysics Data System (ADS)
Kwak, Junha John
Crystallization processes are ubiquitous in nature, science, and technology. Controlling crystal growth is pivotal in many industries as material properties and functions can be tailored by tuning crystal habits (e.g. size, shape, phase). In biomineralization, organisms exert excellent control over bottom-up synthesis and assembly of inorganic-organic structures (e.g. bones, teeth, exoskeletons). This is made possible by growth modifiers that range from small molecules to macromolecules, such as proteins. Molecular recognition of the mineral phase allows proteins to function as nucleation templates, matrices, and growth inhibitors or promoters. We are interested in taking a biomimetic approach to control crystallization via biomolecular growth modifiers. We investigated calcium oxalate monohydrate (COM), found in plants and kidney stones, as a model system of crystallization. We studied the effects of four common proteins on COM crystallization: bovine serum albumin (BSA), transferrin, lactoferrin, and lysozyme. Through kinetic studies of COM crystallization, we classified BSA and lysozyme as COM growth inhibitor and promoter respectively. Their inhibition and promotion effects were also evident in the macroscopic crystal habit. Through adsorption and microscopy experiments, we showed that BSA exhibits binding specificity for the apical surfaces of macroscopic COM crystals. Lysozyme, on the other, functions via a non-binding mechanism at the surface to accelerate the growth of the apical surfaces. We also synthesized and studied peptides derived from the protein primary sequences to identify putative domains responsible for these inhibition and promotion effects. Collectively, our study of physiologically relevant biomolecules suggests potential roles of COM modifiers in pathological crystallization and helps to develop guidelines for rational design of biomolecular growth modifiers for applications in crystal engineering.
Robson, Michael I; de Las Heras, Jose I; Czapiewski, Rafal; Sivakumar, Aishwarya; Kerr, Alastair R W; Schirmer, Eric C
2017-07-01
The 3D organization of the genome changes concomitantly with expression changes during hematopoiesis and immune activation. Studies have focused either on lamina-associated domains (LADs) or on topologically associated domains (TADs), defined by preferential local chromatin interactions, and chromosome compartments, defined as higher-order interactions between TADs sharing functionally similar states. However, few studies have investigated how these affect one another. To address this, we mapped LADs using Lamin B1-DamID during Jurkat T-cell activation, finding significant genome reorganization at the nuclear periphery dominated by release of loci frequently important for T-cell function. To assess how these changes at the nuclear periphery influence wider genome organization, our DamID data sets were contrasted with TADs and compartments. Features of specific repositioning events were then tested by fluorescence in situ hybridization during T-cell activation. First, considerable overlap between TADs and LADs was observed with the TAD repositioning as a unit. Second, A1 and A2 subcompartments are segregated in 3D space through differences in proximity to LADs along chromosomes. Third, genes and a putative enhancer in LADs that were released from the periphery during T-cell activation became preferentially associated with A2 subcompartments and were constrained to the relative proximity of the lamina. Thus, lamina associations influence internal nuclear organization, and changes in LADs during T-cell activation may provide an important additional mode of gene regulation. © 2017 Robson et al.; Published by Cold Spring Harbor Laboratory Press.
NASA Astrophysics Data System (ADS)
Jorand, Rachel; Fehr, Annick; Koch, Andreas; Clauser, Christoph
2011-08-01
In this paper, we present a method that allows one to correct thermal conductivity measurements for the effect of water loss when extrapolating laboratory data to in situ conditions. The water loss in shales and unconsolidated rocks is a serious problem that can introduce errors in the characterization of reservoirs. For this study, we measure the thermal conductivity of four sandstones with and without clay minerals according to different water saturation levels using an optical scanner. Thermal conductivity does not decrease linearly with water saturation. At high saturation and very low saturation, thermal conductivity decreases more quickly because of spontaneous liquid displacement and capillarity effects. Apart from these two effects, thermal conductivity decreases quasi-linearly. We also notice that the samples containing clay minerals are not completely drained, and thermal conductivity reaches a minimum value. In order to fit the variation of thermal conductivity with the water saturation as a whole, we used modified models commonly presented in thermal conductivity studies: harmonic and arithmetic mean and geometric models. These models take into account different types of porosity, especially those attributable to the abundance of clay, using measurements obtained from nuclear magnetic resonance (NMR). For argillaceous sandstones, a modified arithmetic-harmonic model fits the data best. For clean quartz sandstones under low water saturation, the closest fit to the data is obtained with the modified arithmetic-harmonic model, while for high water saturation, a modified geometric mean model proves to be the best.
Developing putative AOPs from high content data Shannon M. Bell1,2, Stephen W. Edwards2 1 Oak Ridge Institute for Science and Education 2 Integrated Systems Toxicology Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development,...
Systems for the Intermodal Routing of Spent Nuclear Fuel
DOE Office of Scientific and Technical Information (OSTI.GOV)
Peterson, Steven K; Liu, Cheng
The safe and secure movement of spent nuclear fuel from shutdown and active reactor facilities to intermediate or long term storage sites may, in some instances, require the use of several modes of transportation to accomplish the move. To that end, a fully operable multi-modal routing system is being developed within Oak Ridge National Laboratory s (ORNL) WebTRAGIS (Transportation Routing Analysis Geographic Information System). This study aims to provide an overview of multi-modal routing, the existing state of the TRAGIS networks, the source data needs, and the requirements for developing structural relationships between various modes to create a suitable systemmore » for modeling the transport of spent nuclear fuel via a multimodal network. Modern transportation systems are comprised of interconnected, yet separate, modal networks. Efficient transportation networks rely upon the smooth transfer of cargoes at junction points that serve as connectors between modes. A key logistical impediment to the shipment of spent nuclear fuel is the absence of identified or designated transfer locations between transport modes. Understanding the potential network impacts on intermodal transportation of spent nuclear fuel is vital for planning transportation routes from origin to destination. By identifying key locations where modes intersect, routing decisions can be made to prioritize cost savings, optimize transport times and minimize potential risks to the population and environment. In order to facilitate such a process, ORNL began the development of a base intermodal network and associated routing code. The network was developed using previous intermodal networks and information from publicly available data sources to construct a database of potential intermodal transfer locations with likely capability to handle spent nuclear fuel casks. The coding development focused on modifying the existing WebTRAGIS routing code to accommodate intermodal transfers and the selection of prioritization constraints and modifiers to determine route selection. The limitations of the current model and future directions for development are discussed, including the current state of information on possible intermodal transfer locations for spent fuel.« less
Schulze, Juerg; Frauenknecht, Tina; Brodmann, Peter; Bagutti, Claudia
2014-01-01
Despite cultivation and seed import bans of genetically modified (GM) oilseed rape (Brassica napus L.), feral GM plants were found growing along railway lines and in port areas at four sites in Switzerland in 2011 and 2012. All GM plants were identified as glyphosate-resistant GM event GT73 (Roundup Ready, Monsanto). The most affected sites were the Rhine port of Basel and the St. Johann freight railway station in Basel. To assess the distribution and intra- and interspecific outcrossing of GM oilseed rape in more detail, we monitored these two sites in 2013. Leaves and seed pods of feral oilseed rape plants, their possible hybridization partners and putative hybrid plants were sampled in monthly intervals and analysed for the presence of transgenes by real-time PCR. Using flow cytometry, we measured DNA contents of cell nuclei to confirm putative hybrids. In total, 2787 plants were sampled. The presence of GT73 oilseed rape could be confirmed at all previously documented sampling locations and was additionally detected at one new sampling location within the Rhine port. Furthermore, we found the glufosinate-resistant GM events MS8xRF3, MS8 and RF3 (all traded as InVigor, Bayer) at five sampling locations in the Rhine port. To our knowledge, this is the first time that feral MS8xRF3, MS8 or RF3 plants were detected in Europe. Real-time PCR analyses of seeds showed outcrossing of GT73 into two non-GM oilseed rape plants, but no outcrossing of transgenes into related wild species was observed. We found no hybrids between oilseed rape and related species. GM plants most frequently occurred at unloading sites for ships, indicating that ship cargo traffic is the main entry pathway for GM oilseed rape. In the future, it will be of major interest to determine the source of GM oilseed rape seeds. PMID:25464509
Schulze, Juerg; Frauenknecht, Tina; Brodmann, Peter; Bagutti, Claudia
2014-01-01
Despite cultivation and seed import bans of genetically modified (GM) oilseed rape (Brassica napus L.), feral GM plants were found growing along railway lines and in port areas at four sites in Switzerland in 2011 and 2012. All GM plants were identified as glyphosate-resistant GM event GT73 (Roundup Ready, Monsanto). The most affected sites were the Rhine port of Basel and the St. Johann freight railway station in Basel. To assess the distribution and intra- and interspecific outcrossing of GM oilseed rape in more detail, we monitored these two sites in 2013. Leaves and seed pods of feral oilseed rape plants, their possible hybridization partners and putative hybrid plants were sampled in monthly intervals and analysed for the presence of transgenes by real-time PCR. Using flow cytometry, we measured DNA contents of cell nuclei to confirm putative hybrids. In total, 2787 plants were sampled. The presence of GT73 oilseed rape could be confirmed at all previously documented sampling locations and was additionally detected at one new sampling location within the Rhine port. Furthermore, we found the glufosinate-resistant GM events MS8xRF3, MS8 and RF3 (all traded as InVigor, Bayer) at five sampling locations in the Rhine port. To our knowledge, this is the first time that feral MS8xRF3, MS8 or RF3 plants were detected in Europe. Real-time PCR analyses of seeds showed outcrossing of GT73 into two non-GM oilseed rape plants, but no outcrossing of transgenes into related wild species was observed. We found no hybrids between oilseed rape and related species. GM plants most frequently occurred at unloading sites for ships, indicating that ship cargo traffic is the main entry pathway for GM oilseed rape. In the future, it will be of major interest to determine the source of GM oilseed rape seeds.
Yap4 PKA- and GSK3-dependent phosphorylation affects its stability but not its nuclear localization.
Pereira, Jorge; Pimentel, Catarina; Amaral, Catarina; Menezes, Regina A; Rodrigues-Pousada, Claudina
2009-12-01
Yap4 is a nuclear-resident transcription factor induced in Saccharomyces cerevisiae when exposed to several stress conditions, which include mild hyperosmotic and oxidative stress, temperature shift or metal exposure. This protein is also phosphorylated. Here we report that this modification is driven by PKA and GSK3. In order to ascertain whether Yap4 is directly or indirectly phosphorylated by PKA, we searched for stress and PKA-related kinases that could phosphorylate Yap4. We show that phosphorylation is independent of the kinases Rim15, Yak1, Sch9, Slt2, Ste20 and Ptk2. In addition, we showed that Yap4 phosphorylation is also abrogated in the triple GSK3 mutant mck1 rim11 yol128c. Furthermore, our data reveal that Yap4 nuclear localization is independent of its phosphorylation state. This protein has several putative phosphorylation sites, but only the mutation of residues T192 and S196 impairs its phosphorylation under different stress conditions. The ability of the non-phosphorylated forms of Yap4 to partially rescue the hog1 severe sensitivity phenotype is not affected, suggesting that Yap4 activity is maintained in the absence of phosphorylation. However, this modification seems to be required for stability of the protein, as the non-phosphorylated form has a shorter half-life than the phosphorylated one.
Sundram, Vasudha; Ganju, Aditya; Hughes, Joshua E.; Khan, Sheema; Chauhan, Subhash C.; Jaggi, Meena
2014-01-01
Over 80% of colon cancer development and progression is a result of the dysregulation of β-catenin signaling pathway. Herein, for the first time, we demonstrate that a serine-threonine kinase, Protein Kinase D1 (PKD1), modulates the functions of β-catenin to suppress colon cancer growth. Analysis of normal and colon cancer tissues reveals downregulation of PKD1 expression in advanced stages of colon cancer and its co-localization with β-catenin in the colon crypts. This PKD1 downregulation corresponds with the aberrant expression and nuclear localization of β-catenin. In-vitro investigation of the PKD1-β-catenin interaction in colon cancer cells reveal that PKD1 overexpression suppresses cell proliferation and clonogenic potential and enhances cell-cell aggregation. We demonstrate that PKD1 directly interacts with β-catenin and attenuates β-catenin transcriptional activity by decreasing nuclear β-catenin levels. Additionally, we show that inhibition of nuclear β-catenin transcriptional activity is predominantly influenced by nucleus targeted PKD1. This subcellular modulation of β-catenin results in enhanced membrane localization of β-catenin and thereby increases cell-cell adhesion. Studies in a xenograft mouse model indicate that PKD1 overexpression delayed tumor appearance, enhanced necrosis and lowered tumor hypoxia. Overall, our results demonstrate a putative tumor-suppressor function of PKD1 in colon tumorigenesis via modulation of β-catenin functions in cells. PMID:25149539
Shen, W C; Selvakumar, D; Stanford, D R; Hopper, A K
1993-09-15
Mutations of the Saccharomyces cerevisiae LOS1 gene cause the accumulation of end matured intron-containing pre-tRNAs at elevated temperatures. In an effort to decipher the role of the LOS1 protein in pre-tRNA splicing, we have analyzed the LOS1 gene and its protein product. The LOS1 gene is located on the left arm of chromosome XI and the order of genes in this area of the chromosome is .... URA1 ... SAC1 TRP3 UBA1 STE6 LOS1 .... FAS1..... The LOS1 open reading frame encodes a putative protein of 1100 amino acids that shows no significant homology to other genes. The LOS1 open reading frame was tagged with the influenza virus hemagglutinin epitope recognized by the 12CA5 antibody. The 12CA5 antibody recognizes an epitope-tagged protein of the size predicted by the LOS1 open reading frame. Using this antibody for indirect immunofluorescence and cell fractionation studies we show that the LOS1 protein is located in nuclei. Los1p cannot be extracted from nuclei by treatment with nucleases, salts, or Triton X-100. This insolubility suggests that Los1p is a component of the nucleoskeleton. We propose that LOS1 mutations may affect pre-tRNA processing via alteration of the nuclear matrix.
Molecular basis of the specific subcellular localization of the C2-like domain of 5-lipoxygenase.
Kulkarni, Shilpa; Das, Sudipto; Funk, Colin D; Murray, Diana; Cho, Wonhwa
2002-04-12
The activation of 5-lipoxygenase (5-LO) involves its calcium-dependent translocation to the nuclear envelope, where it catalyzes the two-step transformation of arachidonic acid into leukotriene A(4), leading to the synthesis of various leukotrienes. To understand the mechanism by which 5-LO is specifically targeted to the nuclear envelope, we studied the membrane binding properties of the amino-terminal domain of 5-LO, which has been proposed to have a C2 domain-like structure. The model building, electrostatic potential calculation, and in vitro membrane binding studies of the isolated C2-like domain of 5-LO and selected mutants show that this Ca(2+)-dependent domain selectively binds zwitterionic phosphatidylcholine, which is conferred by tryptophan residues (Trp(13), Trp(75), and Trp(102)) located in the putative Ca(2+)-binding loops. The spatiotemporal dynamics of the enhanced green fluorescence protein-tagged C2-like domain of 5-LO and mutants in living cells also show that the phosphatidylcholine selectivity of the C2-like domain accounts for the specific targeting of 5-LO to the nuclear envelope. Together, these results show that the C2-like domain of 5-LO is a genuine Ca(2+)-dependent membrane-targeting domain and that the subcellular localization of the domain is governed in large part by its membrane binding properties.
GARNATJE, TERESA; GARCIA, SÒNIA; VILATERSANA, ROSER; VALLÈS, JOAN
2006-01-01
• Background and Aims Plant genome size is an important biological characteristic, with relationships to systematics, ecology and distribution. Currently, there is no information regarding nuclear DNA content for any Carthamus species. In addition to improving the knowledge base, this research focuses on interspecific variation and its implications for the infrageneric classification of this genus. Genome size variation in the process of allopolyploid formation is also addressed. • Methods Nuclear DNA samples from 34 populations of 16 species of the genus Carthamus were assessed by flow cytometry using propidium iodide. • Key Results The 2C values ranged from 2·26 pg for C. leucocaulos to 7·46 pg for C. turkestanicus, and monoploid genome size (1Cx-value) ranged from 1·13 pg in C. leucocaulos to 1·53 pg in C. alexandrinus. Mean genome sizes differed significantly, based on sectional classification. Both allopolyploid species (C. creticus and C. turkestanicus) exhibited nuclear DNA contents in accordance with the sum of the putative parental C-values (in one case with a slight reduction, frequent in polyploids), supporting their hybrid origin. • Conclusions Genome size represents a useful tool in elucidating systematic relationships between closely related species. A considerable reduction in monoploid genome size, possibly due to the hybrid formation, is also reported within these taxa. PMID:16390843
Green, Brian J.; Li, Wei-Ye; Manhart, James R.; Fox, Theodore C.; Summer, Elizabeth J.; Kennedy, Robert A.; Pierce, Sidney K.; Rumpho, Mary E.
2000-01-01
Early in its life cycle, the marine mollusc Elysia chlorotica Gould forms an intracellular endosymbiotic association with chloroplasts of the chromophytic alga Vaucheria litorea C. Agardh. As a result, the dark green sea slug can be sustained in culture solely by photoautotrophic CO2 fixation for at least 9 months if provided with only light and a source of CO2. Here we demonstrate that the sea slug symbiont chloroplasts maintain photosynthetic oxygen evolution and electron transport activity through photosystems I and II for several months in the absence of any external algal food supply. This activity is correlated to the maintenance of functional levels of chloroplast-encoded photosystem proteins, due in part at least to de novo protein synthesis of chloroplast proteins in the sea slug. Levels of at least one putative algal nuclear encoded protein, a light-harvesting complex protein homolog, were also maintained throughout the 9-month culture period. The chloroplast genome of V. litorea was found to be 119.1 kb, similar to that of other chromophytic algae. Southern analysis and polymerase chain reaction did not detect an algal nuclear genome in the slug, in agreement with earlier microscopic observations. Therefore, the maintenance of photosynthetic activity in the captured chloroplasts is regulated solely by the algal chloroplast and animal nuclear genomes. PMID:10982447
Green, B J; Li, W Y; Manhart, J R; Fox, T C; Summer, E J; Kennedy, R A; Pierce, S K; Rumpho, M E
2000-09-01
Early in its life cycle, the marine mollusc Elysia chlorotica Gould forms an intracellular endosymbiotic association with chloroplasts of the chromophytic alga Vaucheria litorea C. Agardh. As a result, the dark green sea slug can be sustained in culture solely by photoautotrophic CO(2) fixation for at least 9 months if provided with only light and a source of CO(2). Here we demonstrate that the sea slug symbiont chloroplasts maintain photosynthetic oxygen evolution and electron transport activity through photosystems I and II for several months in the absence of any external algal food supply. This activity is correlated to the maintenance of functional levels of chloroplast-encoded photosystem proteins, due in part at least to de novo protein synthesis of chloroplast proteins in the sea slug. Levels of at least one putative algal nuclear encoded protein, a light-harvesting complex protein homolog, were also maintained throughout the 9-month culture period. The chloroplast genome of V. litorea was found to be 119.1 kb, similar to that of other chromophytic algae. Southern analysis and polymerase chain reaction did not detect an algal nuclear genome in the slug, in agreement with earlier microscopic observations. Therefore, the maintenance of photosynthetic activity in the captured chloroplasts is regulated solely by the algal chloroplast and animal nuclear genomes.
Wang, Shu; Tao, Qianyi; Pan, Junsong; Si, Longting; Gong, Zhenhui; Cai, Run
2012-01-01
It is well established that the plant hormone ethylene plays a key role in cucumber sex determination. Since the unisexual control gene M was cloned and shown to encode an ethylene synthase, instead of an ethylene receptor, the ‘one-hormone hypothesis’, which was used to explain the cucumber sex phenotype, has been challenged. Here, the physiological function of CsACS2 (the gene encoded by the M locus) was studied using the transgenic tobacco system. The results indicated that overexpression of CsACS2 increased ethylene production in the tobacco plant, and the native cucumber promoter had no activity in transgenic tobacco (PM). However, when PM plants were treated with exogenous ethylene, CsACS2 expression could be detected. In cucumber, ethylene treatment could also induce transcription of CsACS2, while inhibition of ethylene action reduced the expression level. These findings suggest a positive feedback regulation mechanism for CsACS2, and a modified ‘one-hormone hypothesis’ for sex determination in cucumber is proposed. PMID:22577183
Li, Zheng; Wang, Shu; Tao, Qianyi; Pan, Junsong; Si, Longting; Gong, Zhenhui; Cai, Run
2012-07-01
It is well established that the plant hormone ethylene plays a key role in cucumber sex determination. Since the unisexual control gene M was cloned and shown to encode an ethylene synthase, instead of an ethylene receptor, the 'one-hormone hypothesis', which was used to explain the cucumber sex phenotype, has been challenged. Here, the physiological function of CsACS2 (the gene encoded by the M locus) was studied using the transgenic tobacco system. The results indicated that overexpression of CsACS2 increased ethylene production in the tobacco plant, and the native cucumber promoter had no activity in transgenic tobacco (PM). However, when PM plants were treated with exogenous ethylene, CsACS2 expression could be detected. In cucumber, ethylene treatment could also induce transcription of CsACS2, while inhibition of ethylene action reduced the expression level. These findings suggest a positive feedback regulation mechanism for CsACS2, and a modified 'one-hormone hypothesis' for sex determination in cucumber is proposed.
Kim, Jae-Yong; Park, Ki-Hoon; Kim, Jihoe; Choi, Inho; Cho, Kyung-Hyun
2015-01-01
Safety concerns have been raised regarding the association of chronic consumption of artificial sweeteners (ASs) with metabolic disorders, especially in the heart and brain. There has been no information on the in vivo physiological effects of AS consumption in lipoprotein metabolism. High-dosage treatment (final 25, 50, and 100 mM) with AS (aspartame, acesulfame K, and saccharin) to human high-density lipoprotein (HDL) induced loss of antioxidant ability along with elevated atherogenic effects. Aspartame-treated HDL3 (final 100 mM) almost all disappeared due to putative proteolytic degradation. Aspartame- and saccharin-treated HDL3 showed more enhanced cholesteryl ester transfer activity, while their antioxidant ability was disappeared. Microinjection of the modified HDL3 exacerbated the inflammatory death in zebrafish embryos in the presence of oxLDL. These results show that AS treatment impaired the beneficial functions of HDL, resulting in loss of antioxidant and anti-atherogenic activities. These results suggest that aspartame and saccharin could be toxic to the human circulation system as well as embryonic development via impairment of lipoprotein function.
Kim, K H; Hemenway, C
1997-05-26
The putative subgenomic RNA (sgRNA) promoter regions upstream of the potato virus X (PVX) triple block and coat protein (CP) genes contain sequences common to other potexviruses. The importance of these sequences to PVX sgRNA accumulation was determined by inoculation of Nicotiana tabacum NT1 cell suspension protoplasts with transcripts derived from wild-type and modified PVX cDNA clones. Analyses of RNA accumulation by S1 nuclease digestion and primer extension indicated that a conserved octanucleotide sequence element and the spacing between this element and the start-site for sgRNA synthesis are critical for accumulation of the two major sgRNA species. The impact of mutations on CP sgRNA levels was also reflected in the accumulation of CP. In contrast, genomic minus- and plus-strand RNA accumulation were not significantly affected by mutations in these regions. Studies involving inoculation of tobacco plants with the modified transcripts suggested that the conserved octanucleotide element functions in sgRNA accumulation and some other aspect of the infection process.
Reiman, Eric M.
2012-01-01
Alzheimer’s disease (AD) is associated with characteristic and progressive reductions in flourodeoxyglucose positron emission tomography (FDG PET) measurements of the regional cerebral metabolic rate for glucose. These reductions begin years before the onset of symptoms, are correlated with clinical severity, and may help predict an affected patient’s clinical course and neuropathological diagnosis. Like several other AD biomarkers, FDG PET has the potential to accelerate the evaluation of these treatments, particularly in the earliest clinical and preclinical stages. This article considers FDG PET’s role in the detection and tracking of AD, its emerging roles in the evaluation of disease-slowing treatments, some of the issues involved in the acquisition, analysis, and interpretation of FDG PET data, and the evidence needed to help qualify FDG PET and other biomarkers for use in the accelerated approval of AD-slowing treatments. It recommends scientific strategies and public policies to further establish the role of FDG PET and other AD biomarkers in therapeutic trials and find demonstrably effective disease-modifying and presymptomatic AD treatments as quickly as possible. PMID:21983241
Nuclear design of a vapor core reactor for space nuclear propulsion
NASA Astrophysics Data System (ADS)
Dugan, Edward T.; Watanabe, Yoichi; Kuras, Stephen A.; Maya, Isaac; Diaz, Nils J.
1993-01-01
Neutronic analysis methodology and results are presented for the nuclear design of a vapor core reactor for space nuclear propulsion. The Nuclear Vapor Thermal Reactor (NVTR) Rocket Engine uses modified NERVA geometry and systems which the solid fuel replaced by uranium tetrafluoride vapor. The NVTR is an intermediate term gas core thermal rocket engine with specific impulse in the range of 1000-1200 seconds; a thrust of 75,000 lbs for a hydrogen flow rate of 30 kg/s; average core exit temperatures of 3100 K to 3400 K; and reactor thermal powers of 1400 to 1800 MW. Initial calculations were performed on epithermal NVTRs using ZrC fuel elements. Studies are now directed at thermal NVTRs that use fuel elements made of C-C composite. The large ZrC-moderated reactors resulted in thrust-to-weight ratios of only 1 to 2; the compact C-C composite systems yield thrust-to-weight ratios of 3 to 5.
75 FR 73935 - Miscellaneous Administrative Changes
Federal Register 2010, 2011, 2012, 2013, 2014
2010-11-30
... on October 18, 2004 In a petition for rulemaking (PRM) submitted by the Nuclear Energy Institute on... entity regulated by the NRC. Environmental Impact: Categorical Exclusion The NRC has determined that this... modify existing regulations. Therefore, neither an environmental impact statement nor an environmental...
He, Xiangyu; Zhu, Xiaoyu; Wang, Xuexiang; Wang, Wei; Dai, Yu; Yan, Qingfeng
2013-01-01
The phenotypic manifestations of mitochondrial DNA (mtDNA) mutations are modulated by mitochondrial DNA haplotypes, nuclear modifier genes and environmental factors. The yeast mitochondrial 15S rRNA C1477G (P(R) or P(R) 454) mutation corresponds to the human 12S rRNA C1494T and A1555G mutations, which are well known as primary factors for aminoglycoside-induced nonsyndromic deafness. Here we report that the deletion of the nuclear modifier gene MTO2 suppressed the aminoglycoside-sensitivity of mitochondrial 15S rRNA C1477G mutation in Saccharomyces cerevisiae. First, the strain with a single mtDNA C1477G mutation exhibited hypersensitivity to neomycin. Functional assays indicated that the steady-state transcription level of mitochondrial DNA, the mitochondrial respiratory rate, and the membrane potential decreased significantly after neomycin treatment. The impaired mitochondria could not produce sufficient energy to maintain cell viability. Second, when the mto2 null and the mitochondrial C1477G mutations co-existed (mto2(P(R))), the oxygen consumption rate in the double mutant decreased markedly compared to that of the control strains (MTO2(P(S)), mto2(P(S)) and MTO2(P(R))). The expression levels of the key glycolytic genes HXK2, PFK1 and PYK1 in the mto2(P(R)) strain were stimulated by neomycin and up-regulated by 89%, 112% and 55%, respectively. The enhanced glycolysis compensated for the respiratory energy deficits, and could be inhibited by the glycolytic enzyme inhibitor. Our findings in yeast will provide a new insight into the pathogenesis of human deafness.
Implementation of Quantum Private Queries Using Nuclear Magnetic Resonance
NASA Astrophysics Data System (ADS)
Wang, Chuan; Hao, Liang; Zhao, Lian-Jie
2011-08-01
We present a modified protocol for the realization of a quantum private query process on a classical database. Using one-qubit query and CNOT operation, the query process can be realized in a two-mode database. In the query process, the data privacy is preserved as the sender would not reveal any information about the database besides her query information, and the database provider cannot retain any information about the query. We implement the quantum private query protocol in a nuclear magnetic resonance system. The density matrix of the memory registers are constructed.
Heavy quark energy loss in nuclear medium
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Benr-Wei; Wang, Enke; Wang, Xin-Nian
2003-09-16
Multiple scattering, modified fragmentation functions and radiative energy loss of a heavy quark propagating in a nuclear medium are investigated in perturbative QCD. Because of the quark mass dependence of the gluon formation time, the medium size dependence of heavy quark energy loss is found to change from a linear to a quadratic form when the initial energy and momentum scale are increased relative to the quark mass. The radiative energy loss is also significantly suppressed relative to a light quark due to the suppression of collinear gluon emission by a heavy quark.
NASA Astrophysics Data System (ADS)
Koscheev, Vladimir; Manturov, Gennady; Pronyaev, Vladimir; Rozhikhin, Evgeny; Semenov, Mikhail; Tsibulya, Anatoly
2017-09-01
Several k∞ experiments were performed on the KBR critical facility at the Institute of Physics and Power Engineering (IPPE), Obninsk, Russia during the 1970s and 80s for study of neutron absorption properties of Cr, Mn, Fe, Ni, Zr, and Mo. Calculations of these benchmarks with almost any modern evaluated nuclear data libraries demonstrate bad agreement with the experiment. Neutron capture cross sections of the odd isotopes of Cr, Mn, Fe, and Ni in the ROSFOND-2010 library have been reevaluated and another evaluation of the Zr nuclear data has been adopted. Use of the modified nuclear data for Cr, Mn, Fe, Ni, and Zr leads to significant improvement of the C/E ratio for the KBR assemblies. Also a significant improvement in agreement between calculated and evaluated values for benchmarks with Fe reflectors was observed. C/E results obtained with the modified ROSFOND library for complex benchmark models that are highly sensitive to the cross sections of structural materials are no worse than results obtained with other major evaluated data libraries. Possible improvement in results by decreasing the capture cross section for Zr and Mo at the energies above 1 keV is indicated.
Zhang, X L; Su, G F; Yuan, H Y; Chen, J G; Huang, Q Y
2014-09-15
Atmospheric dispersion models play an important role in nuclear power plant accident management. A reliable estimation of radioactive material distribution in short range (about 50 km) is in urgent need for population sheltering and evacuation planning. However, the meteorological data and the source term which greatly influence the accuracy of the atmospheric dispersion models are usually poorly known at the early phase of the emergency. In this study, a modified ensemble Kalman filter data assimilation method in conjunction with a Lagrangian puff-model is proposed to simultaneously improve the model prediction and reconstruct the source terms for short range atmospheric dispersion using the off-site environmental monitoring data. Four main uncertainty parameters are considered: source release rate, plume rise height, wind speed and wind direction. Twin experiments show that the method effectively improves the predicted concentration distribution, and the temporal profiles of source release rate and plume rise height are also successfully reconstructed. Moreover, the time lag in the response of ensemble Kalman filter is shortened. The method proposed here can be a useful tool not only in the nuclear power plant accident emergency management but also in other similar situation where hazardous material is released into the atmosphere. Copyright © 2014 Elsevier B.V. All rights reserved.
Cell death in the pathogenesis of systemic lupus erythematosus and lupus nephritis.
Mistry, Pragnesh; Kaplan, Mariana J
2017-12-01
Nephritis is one of the most severe complications of systemic lupus erythematosus (SLE). One key characteristic of lupus nephritis (LN) is the deposition of immune complexes containing nucleic acids and/or proteins binding to nucleic acids and autoantibodies recognizing these molecules. A variety of cell death processes are implicated in the generation and externalization of modified nuclear autoantigens and in the development of LN. Among these processes, apoptosis, primary and secondary necrosis, NETosis, necroptosis, pyroptosis, and autophagy have been proposed to play roles in tissue damage and immune dysregulation. Cell death occurs in healthy individuals during conditions of homeostasis yet autoimmunity does not develop, at least in part, because of rapid clearance of dying cells. In SLE, accelerated cell death combined with a clearance deficiency may lead to the accumulation and externalization of nuclear autoantigens and to autoantibody production. In addition, specific types of cell death may modify autoantigens and alter their immunogenicity. These modified molecules may then become novel targets of the immune system and promote autoimmune responses in predisposed hosts. In this review, we examine various cell death pathways and discuss how enhanced cell death, impaired clearance, and post-translational modifications of proteins could contribute to the development of lupus nephritis. Published by Elsevier Inc.
Zheng, Hao; Tang, Cui; Yin, Chunhua
2015-06-01
Present study aimed at exploring advantages/disadvantages of amino acid modified trimethylated chitosan in conquering multiple gene delivery obstacles and thus providing comprehensive understandings for improved transfection efficiency. Arginine, cysteine, and histidine modified trimethyl chitosan were synthesized and employed to self-assemble with plasmid DNA (pDNA) to form nanocomplexes, namely TRNC, TCNC, and THNC, respectively. They were assessed by structural stability, cellular uptake, endosomal escape, release behavior, nuclear localization, and in vitro and in vivo transfection efficiencies. Besides, sodium tripolyphosphate (TPP) was added into TRNC to compromise certain disadvantageous attributes for pDNA delivery. Optimal endosomal escape ability failed to bring in satisfactory transfection efficiency of THNC due to drawbacks in structural stability, cellular uptake, pDNA liberation, and nuclear distribution. TCNC evoked the most potent gene expression owing to multiple advantages including sufficient stability, preferable uptake, efficient pDNA release, and high nucleic accumulation. Undesirable stability and insufficient pDNA release adversely affected TRNC-mediated gene transfer. However, incorporation of TPP could improve such disadvantages and consequently resulted in enhanced transfection efficiencies. Coordination of multiple contributing effects to conquer all delivery obstacles was necessitated for improved transfection efficiency, which would provide insights into rational design of gene delivery vehicles.
Design of selective nuclear receptor modulators: RAR and RXR as a case study.
de Lera, Angel R; Bourguet, William; Altucci, Lucia; Gronemeyer, Hinrich
2007-10-01
Retinoic acid receptors (RARs) and retinoid X receptors (RXRs) are members of the nuclear receptor superfamily whose effects on cell growth and survival can be modulated therapeutically by small-molecule ligands. Although compounds that target these receptors are powerful anticancer drugs, their use is limited by toxicity. An improved understanding of the structural biology of RXRs and RARs and recent advances in the chemical synthesis of modified retinoid and rexinoid ligands should enable the rational design of more selective agents that might overcome such problems. Here, we review structural data for RXRs and RARs, discuss strategies in the design of selective RXR and RAR modulators, and consider lessons that can be learned for the design of selective nuclear-receptor modulators in general.
Reactivity control assembly for nuclear reactor. [LMFBR
Bollinger, L.R.
1982-03-17
This invention, which resulted from a contact with the United States Department of Energy, relates to a control mechanism for a nuclear reactor and, more particularly, to an assembly for selectively shifting different numbers of reactivity modifying rods into and out of the core of a nuclear reactor. It has been proposed heretofore to control the reactivity of a breeder reactor by varying the depth of insertion of control rods (e.g., rods containing a fertile material such as ThO/sub 2/) in the core of the reactor, thereby varying the amount of neutron-thermalizing coolant and the amount of neutron-capturing material in the core. This invention relates to a mechanism which can advantageously be used in this type of reactor control system.
Nucleoporins and chromatin metabolism.
Ptak, Christopher; Wozniak, Richard W
2016-06-01
Mounting evidence has implicated a group of proteins termed nucleoporins, or Nups, in various processes that regulate chromatin structure and function. Nups were first recognized as building blocks for nuclear pore complexes, but several members of this group of proteins also reside in the cytoplasm and within the nucleus. Moreover, many are dynamic and move between these various locations. Both at the nuclear envelope, as part of nuclear pore complexes, and within the nucleoplasm, Nups interact with protein complexes that function in gene transcription, chromatin remodeling, DNA repair, and DNA replication. Here, we review recent studies that provide further insight into the molecular details of these interactions and their role in regulating the activity of chromatin modifying factors. Copyright © 2016. Published by Elsevier Ltd.
NASA Astrophysics Data System (ADS)
Voronchev, V. T.; Kukulin, V. I.
2000-12-01
An original extrapolation technique developed previously is modified and applied to study nuclear reactions in the 6Li + T system at energies E = 0-2 MeV. Cross sections of gamma-ray-producing reactions 6Li(t,d1)7Li*[0.478] and 6Li(t,p1)8Li*[0.981] with important diagnostic implications are calculated. The (t,d1) nuclear data found exceed those accepted elsewhere by 2.5-3.5 times at sub-barrier energies. The cross sections of the (t,p1) reaction are calculated for the first time.
Nuclear Weak Rates and Detailed Balance in Stellar Conditions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Misch, G. Wendell, E-mail: wendell@sjtu.edu, E-mail: wendell.misch@gmail.com
Detailed balance is often invoked in discussions of nuclear weak transitions in astrophysical environments. Satisfaction of detailed balance is rightly touted as a virtue of some methods of computing nuclear transition strengths, but I argue that it need not necessarily be strictly obeyed in astrophysical environments, especially when the environment is far from weak equilibrium. I present the results of shell model calculations of nuclear weak strengths in both charged-current and neutral-current channels at astrophysical temperatures, finding some violation of detailed balance. I show that a slight modification of the technique to strictly obey detailed balance has little effect onmore » the reaction rates associated with these strengths under most conditions, though at high temperature the modified technique in fact misses some important strength. I comment on the relationship between detailed balance and weak equilibrium in astrophysical conditions.« less
Progress in Electromagnetic Alteration of Nuclear Decay Properties
NASA Astrophysics Data System (ADS)
Casperson, R. J.; Hughes, R. O.; Burke, J. T.; Scielzo, N. D.; Soufli, R.
2014-03-01
Significant alteration of nuclear decay properties would have important consequences, ranging from novel approaches to nuclear batteries and gamma-ray lasers, to improved viability for physics experiments with short-lived targets. Quantum systems that decay by photon emission must couple to the electromagnetic modes of the local environment, and by modifying these modes, one can manipulate the rate of spontaneous emission. The nuclear isomer 235mU is low-energy, long-lived, and is easily populated through 239Pu α-decay, which makes it an excellent benchmark for this effect. The decay rate of this isomer in a variety of environments is currently under investigation. Implications of this work will be discussed, and first results will be presented. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.
Progress in Electromagnetic Alteration of Nuclear Decay Properties
NASA Astrophysics Data System (ADS)
Casperson, R. J.; Burke, J. T.; Hughes, R. O.; Scielzo, N. D.; Soufli, R.
2013-10-01
Significant alteration of nuclear decay properties would have important consequences, ranging from novel approaches to nuclear batteries and gamma-ray lasers, to improved viability for physics experiments with short-lived targets. Quantum systems that decay by photon emission must couple to the electromagnetic modes of the local environment, and by modifying these modes, one can manipulate the rate of spontaneous emission. The nuclear isomer 235mU is low-energy, long-lived, and is easily populated through 239Pu α-decay, which makes it an excellent benchmark for this effect. The decay rate of this isomer in a variety of environments is currently under investigation. Implications of this work will be discussed, and first results will be presented. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.
Taddei, Angela; Schober, Heiko; Gasser, Susan M.
2010-01-01
The budding yeast nucleus, like those of other eukaryotic species, is highly organized with respect to both chromosomal sequences and enzymatic activities. At the nuclear periphery interactions of nuclear pores with chromatin, mRNA, and transport factors promote efficient gene expression, whereas centromeres, telomeres, and silent chromatin are clustered and anchored away from pores. Internal nuclear organization appears to be function-dependent, reflecting localized sites for tRNA transcription, rDNA transcription, ribosome assembly, and DNA repair. Recent advances have identified new proteins involved in the positioning of chromatin and have allowed testing of the functional role of higher-order chromatin organization. The unequal distribution of silent information regulatory factors and histone modifying enzymes, which arises in part from the juxtaposition of telomeric repeats, has been shown to influence chromatin-mediated transcriptional repression. Other localization events suppress unwanted recombination. These findings highlight the contribution budding yeast genetics and cytology have made to dissecting the functional role of nuclear structure. PMID:20554704
In situ mechanical characterization of the cell nucleus by atomic force microscopy.
Liu, Haijiao; Wen, Jun; Xiao, Yun; Liu, Jun; Hopyan, Sevan; Radisic, Milica; Simmons, Craig A; Sun, Yu
2014-04-22
The study of nuclear mechanical properties can provide insights into nuclear dynamics and its role in cellular mechanotransduction. While several methods have been developed to characterize nuclear mechanical properties, direct intracellular probing of the nucleus in situ is challenging. Here, a modified AFM (atomic force microscopy) needle penetration technique is demonstrated to mechanically characterize cell nuclei in situ. Cytoplasmic and nuclear stiffness were determined based on two different segments on the AFM indentation curves and were correlated with simultaneous confocal Z-stack microscopy reconstructions. On the basis of direct intracellular measurement, we show that the isolated nuclei from fibroblast-like cells exhibited significantly lower Young's moduli than intact nuclei in situ. We also show that there is in situ nucleus softening in the highly metastatic bladder cancer cell line T24 when compared to its less metastatic counterpart RT4. This technique has potential to become a reliable quantitative measurement tool for intracellular mechanics studies.
Optimized surface topography of thermoplastics blends modified by graphene
DOE Office of Scientific and Technical Information (OSTI.GOV)
Joshi, Girish M., E-mail: varadgm@gmail.com, E-mail: girish.joshi@vit.ac.in; Sharma, Ajay; Pandey, Mayank
2016-05-23
Polyacrilonitrile (PAN)/ Polyvinylfloride (PVDF) blends were modified by loading the graphene (0.5 to 1.5 wt %). The presence of graphene reveals the interesting surface properties. The decrease in surface roughness as function of graphene loading was confirmed by the topographic method of recording (two and three dimensional images) with atomic force microscope (AFM). The blends become smoother in nature due to occupied smaller surface area of graphene. This property may be useful for several applications in the marine, naval, nuclear domain and engineering applications as barrier medium.
NASA Astrophysics Data System (ADS)
Khezri, Khezrollah; Fazli, Yousef
2017-10-01
Hydrophilic silica aerogel nanoparticles surface was modified with hexamethyldisilazane. Then, the resultant modified nanoparticles were used in random copolymerization of styrene and butyl acrylate via activators generated by electron transfer for atom transfer radical polymerization. Conversion and molecular weight determinations were performed using gas and size exclusion chromatography respectively. Addition of modified nanoparticles by 3 wt% results in a decrease of conversion from 68 to 46 %. Molecular weight of copolymer chains decreases from 12,500 to 7,500 g.mol-1 by addition of 3 wt% modified nanoparticles; however, PDI values increase from 1.1 to 1.4. Proton nuclear magnetic resonance spectroscopy results indicate that the molar ratio of each monomer in the copolymer chains is approximately similar to the initial selected mole ratio of them. Increasing thermal stability of the nanocomposites is demonstrated by thermal gravimetric analysis. Differential scanning calorimetry also shows a decrease in glass transition temperature by increasing modified silica aerogel nanoparticles.
Coleman, Neil M; Abramson, Lee R; Coleman, Fiona A B
2012-03-01
This study examines the past and future impact of nuclear reactors on anthropogenic carbon emissions to the atmosphere. If nuclear power had never been commercially developed, what additional global carbon emissions would have occurred? More than 44 y of global nuclear power have caused a lag time of at least 1.2 y in carbon emissions and CO2 concentrations through the end of 2009. This lag time incorporates the contribution of life cycle carbon emissions due to the construction and operation of nuclear plants. Cumulative global carbon emissions would have been about 13 Gt greater through 2009, and the mean annual CO2 concentration at Mauna Loa would have been ~2.7 ppm greater than without nuclear power. This study finds that an additional 14–17 Gt of atmospheric carbon emissions could be averted by the global use of nuclear power through 2030, for a cumulative total of 27–30 Gt averted during the period 1965–2030. This result is based on International Atomic Energy Agency projections of future growth in nuclear power from 2009–2030, modified by the recent loss or permanent shutdown of 14 reactors in Japan and Germany
Uranium extraction: Fuel from seawater
Tsouris, Costas; Oak Ridge National Lab.
2017-02-17
Over four billion tonnes of uranium are currently in the oceans that could be harvested for nuclear fuel, but current capture methods have limited performance and reusability. Now, an electrochemical method using modified carbon electrodes is shown to be promising for the extraction of uranium from seawater.
Chemo-enzymatic synthesis of physiologically modified avenanthramides
USDA-ARS?s Scientific Manuscript database
Avenanthramides are a group of phenolic alkaloids produced, among food crops, uniquely by oats. These metabolites function as phytoalexins in vegetative tissue and they are produced in the grain where their function is unknown. In vitro the avenanthramides inhibit the activation of nuclear factor ka...
Hyperon stars in a modified quark meson coupling model
NASA Astrophysics Data System (ADS)
Mishra, R. N.; Sahoo, H. S.; Panda, P. K.; Barik, N.; Frederico, T.
2016-09-01
We determine the equation of state (EOS) of nuclear matter with the inclusion of hyperons in a self-consistent manner by using a modified quark meson coupling model where the confining interaction for quarks inside a baryon is represented by a phenomenological average potential in an equally mixed scalar-vector harmonic form. The hadron-hadron interaction in nuclear matter is then realized by introducing additional quark couplings to σ ,ω , and ρ mesons through mean-field approximations. The effect of a nonlinear ω -ρ term on the EOS is studied. The hyperon couplings are fixed from the optical potential values and the mass-radius curve is determined satisfying the maximum mass constraint of 2 M⊙ for neutron stars, as determined in recent measurements of the pulsar PSR J0348+0432. We also observe that there is no significant advantage of introducing the nonlinear ω -ρ term in the context of obtaining the star mass constraint in the present set of parametrizations.
Neutron transport analysis for nuclear reactor design
Vujic, Jasmina L.
1993-01-01
Replacing regular mesh-dependent ray tracing modules in a collision/transfer probability (CTP) code with a ray tracing module based upon combinatorial geometry of a modified geometrical module (GMC) provides a general geometry transfer theory code in two dimensions (2D) for analyzing nuclear reactor design and control. The primary modification of the GMC module involves generation of a fixed inner frame and a rotating outer frame, where the inner frame contains all reactor regions of interest, e.g., part of a reactor assembly, an assembly, or several assemblies, and the outer frame, with a set of parallel equidistant rays (lines) attached to it, rotates around the inner frame. The modified GMC module allows for determining for each parallel ray (line), the intersections with zone boundaries, the path length between the intersections, the total number of zones on a track, the zone and medium numbers, and the intersections with the outer surface, which parameters may be used in the CTP code to calculate collision/transfer probability and cross-section values.
Neutron transport analysis for nuclear reactor design
Vujic, J.L.
1993-11-30
Replacing regular mesh-dependent ray tracing modules in a collision/transfer probability (CTP) code with a ray tracing module based upon combinatorial geometry of a modified geometrical module (GMC) provides a general geometry transfer theory code in two dimensions (2D) for analyzing nuclear reactor design and control. The primary modification of the GMC module involves generation of a fixed inner frame and a rotating outer frame, where the inner frame contains all reactor regions of interest, e.g., part of a reactor assembly, an assembly, or several assemblies, and the outer frame, with a set of parallel equidistant rays (lines) attached to it, rotates around the inner frame. The modified GMC module allows for determining for each parallel ray (line), the intersections with zone boundaries, the path length between the intersections, the total number of zones on a track, the zone and medium numbers, and the intersections with the outer surface, which parameters may be used in the CTP code to calculate collision/transfer probability and cross-section values. 28 figures.
Materials characterization with MeV ions
NASA Astrophysics Data System (ADS)
Conlon, T. W.
1989-04-01
The inherent atomic and nuclear properties of energetic ions in materials can be exploited to characterize as well as to modify materials' properties. In nuclear reactors keV ions from neutron collisions damage containment materials. However, basic studies of the interactions of such ions has yielded improved understanding of their properties and has even led to a tailoring of conditions so that the ions can be made to beneficially modify structures (by ion implantation). At higher energies an understanding of the ion-material interaction provides techniques such as PIXE, RBS, and ERD for nondestructive analysis, either in broad beam or "microbeam" mode. At high energies still penetration of the Coulomb barrier opens up activation methods for materials' characterization (CPAA, NRA, TLA etc.). A short discussion of the general properties of energetic ions in materials is followed by a brief introduction to our generic work in these areas, and some examples of current work in the areas of: activation for the radioisotope labelling of nonmetals, mass resolved ERDA using TOF techniques and submicron MeV microprobes.
The putative roles of the ubiquitin/proteasome pathway in resistance to anticancer therapy.
Smith, Laura; Lind, Michael J; Drew, Philip J; Cawkwell, Lynn
2007-11-01
The ubiquitin/proteasome (UP) pathway plays a significant role in many important biological functions and alterations in this pathway have been shown to contribute to the pathology of many human diseases, including cancer. Proteasome inhibition has been well established as a rational strategy for the treatment of multiple myeloma and is currently under investigation for the treatment of other haematological malignancies and solid tumours. Recent evidence suggests that proteasome inhibition may also sensitise tumour cells to the actions of both conventional chemotherapy and radiotherapy, suggesting that this pathway may modify clinical response to anticancer therapy. However, conflicting evidence exists as to the roles of the UP pathway in resistance to treatment. This review endeavours to discuss such roles.
Genetics and the Placebo Effect: the Placebome
Hall, Kathryn T.; Loscalzo, Joseph; Kaptchuk, Ted J.
2015-01-01
Placebos are indispensable controls in randomized clinical trials (RCTs), and placebo responses significantly contribute to routine clinical outcomes. Recent neurophysiological studies reveal neurotransmitter pathways that mediate placebo effects. Evidence that genetic variations in these pathways can modify placebo effects raises the possibility of using genetic screening to identify placebo responders and thereby increase RCT efficacy and improve therapeutic care. Furthermore, the possibility of interaction between placebo and drug molecular pathways warrants consideration in RCT design. The study of genomic effects on placebo response, “the placebome”, is in its infancy. Here, we review evidence from placebo studies and RCTs to identify putative genes in the placebome, examine evidence for placebo-drug interactions, and discuss implications for RCTs and clinical care. PMID:25883069
Itinerant ferromagnetism in an interacting Fermi gas with mass imbalance
NASA Astrophysics Data System (ADS)
von Keyserlingk, C. W.; Conduit, G. J.
2011-05-01
We study the emergence of itinerant ferromagnetism in an ultracold atomic gas with a variable mass ratio between the up- and down-spin species. Mass imbalance breaks the SU(2) spin symmetry, leading to a modified Stoner criterion. We first elucidate the phase behavior in both the grand canonical and canonical ensembles. Second, we apply the formalism to a harmonic trap to demonstrate how a mass imbalance delivers unique experimental signatures of ferromagnetism. These could help future experiments to better identify the putative ferromagnetic state. Furthermore, we highlight how a mass imbalance suppresses the three-body loss processes that handicap the formation of a ferromagnetic state. Finally, we study the time-dependent formation of the ferromagnetic phase following a quench in the interaction strength.
Bellon, L; Maloney, L; Zinnen, S P; Sandberg, J A; Johnson, K E
2000-08-01
Versatile bioanalytical assays to detect chemically stabilized hammerhead ribozyme and putative ribozyme metabolites from plasma are described. The extraction protocols presented are based on serial solid-phase extractions performed on a 96-well plate format and are compatible with either IEX-HPLC or CGE back-end analysis. A validation of both assays confirmed that both the HPLC and the CGE methods possess the required linearity, accuracy, and precision to accurately measure concentrations of hammerhead ribozyme extracted from plasma. These methods should be of general use to detect and quantitate ribozymes from other biological fluids such as serum and urine. Copyright 2000 Academic Press.
Age-dependent α-synuclein aggregation in the Microcebus murinus lemur primate
Canron, Marie-Hélène; Perret, Martine; Vital, Anne; Bézard, Erwan; Dehay, Benjamin
2012-01-01
Since age-dependent deposition of Aβ-amyloid has been reported in the Microcebus murinus, we posited that this animal could as well be a model of age-related synucleinopathy. We characterized the distribution of Aβ-amyloid, α-synuclein and two of its modified forms in the brain of Microcebus murinus aged from 1.5 to 10 years. Intracytoplasmic α-synuclein aggregates were observed only in aged animals in different brain regions, which were also phospho-Ser129 and nitrated α-synuclein immunoreactive. Age-dependent α-synuclein aggregation occurs spontaneously in mouse lemur primates. Microcebus murinus may provide a model to study age-associated α-synucleinopathy and for testing putative therapeutic interventions for both Alzheimer's and Parkinson's diseases. PMID:23205271
SkyNet: A Modular Nuclear Reaction Network Library
NASA Astrophysics Data System (ADS)
Lippuner, Jonas; Roberts, Luke F.
2017-12-01
Almost all of the elements heavier than hydrogen that are present in our solar system were produced by nuclear burning processes either in the early universe or at some point in the life cycle of stars. In all of these environments, there are dozens to thousands of nuclear species that interact with each other to produce successively heavier elements. In this paper, we present SkyNet, a new general-purpose nuclear reaction network that evolves the abundances of nuclear species under the influence of nuclear reactions. SkyNet can be used to compute the nucleosynthesis evolution in all astrophysical scenarios where nucleosynthesis occurs. SkyNet is free and open source, and aims to be easy to use and flexible. Any list of isotopes can be evolved, and SkyNet supports different types of nuclear reactions. SkyNet is modular so that new or existing physics, like nuclear reactions or equations of state, can easily be added or modified. Here, we present in detail the physics implemented in SkyNet with a focus on a self-consistent transition to and from nuclear statistical equilibrium to non-equilibrium nuclear burning, our implementation of electron screening, and coupling of the network to an equation of state. We also present comprehensive code tests and comparisons with existing nuclear reaction networks. We find that SkyNet agrees with published results and other codes to an accuracy of a few percent. Discrepancies, where they exist, can be traced to differences in the physics implementations.
Lammerding, Jan
2015-01-01
The nucleus is the distinguishing feature of eukaryotic cells. Until recently, it was often considered simply as a unique compartment containing the genetic information of the cell and associated machinery, without much attention to its structure and mechanical properties. This article provides compelling examples that illustrate how specific nuclear structures are associated with important cellular functions, and how defects in nuclear mechanics can cause a multitude of human diseases. During differentiation, embryonic stem cells modify their nuclear envelope composition and chromatin structure, resulting in stiffer nuclei that reflect decreased transcriptional plasticity. In contrast, neutrophils have evolved characteristic lobulated nuclei that increase their physical plasticity, enabling passage through narrow tissue spaces in their response to inflammation. Research on diverse cell types further demonstrates how induced nuclear deformations during cellular compression or stretch can modulate cellular function. Pathological examples of disturbed nuclear mechanics include the many diseases caused by mutations in the nuclear envelope proteins lamin A/C and associated proteins, as well as cancer cells that are often characterized by abnormal nuclear morphology. In this article, we will focus on determining the functional relationship between nuclear mechanics and cellular (dys-)function, describing the molecular changes associated with physiological and pathological examples, the resulting defects in nuclear mechanics, and the effects on cellular function. New insights into the close relationship between nuclear mechanics and cellular organization and function will yield a better understanding of normal biology and will offer new clues into therapeutic approaches to the various diseases associated with defective nuclear mechanics. PMID:23737203
Weiserová, Marie; Ryu, Junichi
2008-06-27
Type I restriction-modification (R-M) systems are the most complex restriction enzymes discovered to date. Recent years have witnessed a renaissance of interest in R-M enzymes Type I. The massive ongoing sequencing programmes leading to discovery of, so far, more than 1 000 putative enzymes in a broad range of microorganisms including pathogenic bacteria, revealed that these enzymes are widely represented in nature. The aim of this study was characterisation of a putative R-M system EcoA0ORF42P identified in the commensal Escherichia coli A0 34/86 (O83: K24: H31) strain, which is efficiently used at Czech paediatric clinics for prophylaxis and treatment of nosocomial infections and diarrhoea of preterm and newborn infants. We have characterised a restriction-modification system EcoA0ORF42P of the commensal Escherichia coli strain A0 34/86 (O83: K24: H31). This system, designated as EcoAO83I, is a new functional member of the Type IB family, whose specificity differs from those of known Type IB enzymes, as was demonstrated by an immunological cross-reactivity and a complementation assay. Using the plasmid transformation method and the RM search computer program, we identified the DNA recognition sequence of the EcoAO83I as GGA(8N)ATGC. In consistence with the amino acids alignment data, the 3' TRD component of the recognition sequence is identical to the sequence recognized by the EcoEI enzyme. The A-T (modified adenine) distance is identical to that in the EcoAI and EcoEI recognition sites, which also indicates that this system is a Type IB member. Interestingly, the recognition sequence we determined here is identical to the previously reported prototype sequence for Eco377I and its isoschizomers. Putative restriction-modification system EcoA0ORF42P in the commensal Escherichia coli strain A0 34/86 (O83: K24: H31) was found to be a member of the Type IB family and was designated as EcoAO83I. Combination of the classical biochemical and bacterial genetics approaches with comparative genomics might contribute effectively to further classification of many other putative Type-I enzymes, especially in clinical samples.
Non-viral RNA chimeric antigen receptor modified T cells in patients with Hodgkin lymphoma.
Svoboda, Jakub; Rheingold, Susan R; Gill, Saar I; Grupp, Stephan A; Lacey, Simon F; Kulikovskaya, Irina; Suhoski, Megan M; Melenhorst, J Joseph; Loudon, Brandon; Mato, Anthony R; Nasta, Sunita Dwivedy; Landsburg, Daniel J; Youngman, Matthew R; Levine, Bruce L; Porter, David L; June, Carl H; Schuster, Stephen J
2018-06-20
Chimeric antigen receptor (CAR) modified T cells are being investigated in many settings including classical Hodgkin lymphoma (cHL). The unique biology of cHL, characterized by scant Hodgkin and Reed-Sternberg (HRS) cells within an immunosuppressive tumor microenvironment (TME), may pose challenges for cellular therapies directly targeting antigens expressed on HRS. We hypothesized that eradicating CD19 positive (+) B cells within the TME and the putative circulating CD19+ HRS clonotypic cells using anti-CD19 directed CAR modified T cells (CART19) may indirectly affect HRS cells, which do not express CD19. Here we describe our pilot trial using CART19 in patients with relapsed and refractory cHL. To limit potential toxicities, we used non-viral RNA CART19 cells which are expected to express CAR protein only a few days, as opposed to CART19 generated by viral vector transduction, which expand in vivo and retain CAR expression. All 5 enrolled patients underwent successful manufacturing of non-viral RNA CART19 and 4 were infused with protocol specified cell dose. There were no severe toxicities. Responses were seen, but these were transient. To our knowledge, this is the first CART19 clinical trial to use non-viral RNA gene delivery. This trial was registered at www.clinicaltrials.gov as NCT02277522 (adult) and NCT02624258 (pediatric). Copyright © 2018 American Society of Hematology.
Mruczek, Ryan E. B.
2012-01-01
The cerebral cortex is composed of many distinct classes of neurons. Numerous studies have demonstrated corresponding differences in neuronal properties across cell types, but these comparisons have largely been limited to conditions outside of awake, behaving animals. Thus the functional role of the various cell types is not well understood. Here, we investigate differences in the functional properties of two widespread and broad classes of cells in inferior temporal cortex of macaque monkeys: inhibitory interneurons and excitatory projection cells. Cells were classified as putative inhibitory or putative excitatory neurons on the basis of their extracellular waveform characteristics (e.g., spike duration). Consistent with previous intracellular recordings in cortical slices, putative inhibitory neurons had higher spontaneous firing rates and higher stimulus-evoked firing rates than putative excitatory neurons. Additionally, putative excitatory neurons were more susceptible to spike waveform adaptation following very short interspike intervals. Finally, we compared two functional properties of each neuron's stimulus-evoked response: stimulus selectivity and response latency. First, putative excitatory neurons showed stronger stimulus selectivity compared with putative inhibitory neurons. Second, putative inhibitory neurons had shorter response latencies compared with putative excitatory neurons. Selectivity differences were maintained and latency differences were enhanced during a visual search task emulating more natural viewing conditions. Our results suggest that short-latency inhibitory responses are likely to sculpt visual processing in excitatory neurons, yielding a sparser visual representation. PMID:22933717
Kawai, Takashi; Yamada, Hiroshi; Sato, Nobuya; Takada, Masahiko; Matsumoto, Masayuki
2018-05-02
The dorsal anterior cingulate cortex (dACC) plays crucial roles in monitoring the outcome of a choice and adjusting a subsequent choice behavior based on the outcome information. In the present study, we investigated how different types of dACC neurons, that is, putative pyramidal neurons and putative inhibitory interneurons, contribute to these processes. We analyzed single-unit database obtained from the dACC in monkeys performing a reversal learning task. The monkey was required to adjust choice behavior from past outcome experiences. Depending on their action potential waveforms, the recorded neurons were classified into putative pyramidal neurons and putative inhibitory interneurons. We found that these neurons do not equally contribute to outcome monitoring and behavioral adjustment. Although both neuron types evenly responded to the current outcome, a larger proportion of putative inhibitory interneurons than putative pyramidal neurons stored the information about the past outcome. The putative inhibitory interneurons further represented choice-related signals more frequently, such as whether the monkey would shift the last choice to an alternative at the next choice opportunity. Our findings suggest that putative inhibitory interneurons, which are thought not to project to brain areas outside the dACC, preferentially transmit signals that would adjust choice behavior based on past outcome experiences.
The Putative Son's Attractiveness Alters the Perceived Attractiveness of the Putative Father.
Prokop, Pavol
2015-08-01
A body of literature has investigated female mate choice in the pre-mating context (pre-mating sexual selection). Humans, however, are long-living mammals forming pair-bonds which sequentially produce offspring. Post-mating evaluations of a partner's attractiveness may thus significantly influence the reproductive success of men and women. I tested herein the theory that the attractiveness of putative sons provides extra information about the genetic quality of fathers, thereby influencing fathers' attractiveness across three studies. As predicted, facially attractive boys were more frequently attributed to attractive putative fathers and vice versa (Study 1). Furthermore, priming with an attractive putative son increased the attractiveness of the putative father with the reverse being true for unattractive putative sons. When putative fathers were presented as stepfathers, the effect of the boy's attractiveness on the stepfather's attractiveness was lower and less consistent (Study 2). This suggests that the presence of an attractive boy has the strongest effect on the perceived attractiveness of putative fathers rather than on non-fathers. The generalized effect of priming with beautiful non-human objects also exists, but its effect is much weaker compared with the effects of putative biological sons (Study 3). Overall, this study highlighted the importance of post-mating sexual selection in humans and suggests that the heritable attractive traits of men are also evaluated by females after mating and/or may be used by females in mate poaching.
The evolutionary history of Lygodactylus lizards in the South American open diagonal.
Lanna, Flávia M; Werneck, Fernanda P; Gehara, Marcelo; Fonseca, Emanuel M; Colli, Guarino R; Sites, Jack W; Rodrigues, Miguel T; Garda, Adrian A
2018-06-12
The Pleistocenic Arc Hypothesis (PAH) posits that South American Seasonally Dry Tropical Forests (SDTF) were interconnected during Pleistocene glacial periods, enabling the expansion of species ranges that were subsequently fragmented in interglacial periods, promoting speciation. The lizard genus Lygodactylus occurs in Africa, Madagascar, and South America. Compared to the high diversity of African Lygodactylus, only two species are known to occur in South America, L. klugei and L. wetzeli, distributed in SDTFs and the Chaco, respectively. We use a phylogenetic approach based on mitochondrial (ND2) and nuclear (RAG-1) markers covering the known range of South American Lygodactylus to investigate (i) if they are monophyletic relative to their African congeners, (ii) if their divergence is congruent with the fragmentation of the PAH, and (iii) if cryptic diversity exists within currently recognized species. Maximum likelihood and Bayesian phylogenetic analyses recovered a well-supported monophyletic South American Lygodactylus, presumably resulting from a single trans-Atlantic dispersal event 29 Mya. Species delimitation analyses supported the existence of five putative species, three of them undescribed. Divergence times among L. klugei and the three putative undescribed species, all endemic to the SDTFs, are not congruent with the fragmentation of the PAH. However, fragmentation of the once broader and continuous SDTFs likely influenced the divergence of L. wetzeli in the Chaco and Lygodactylus sp. 3 (in a SDTF enclave in the Cerrado). Copyright © 2018. Published by Elsevier Inc.
Genetic analysis of hybridization and introgression between wild mongoose and brown lemurs.
Pastorini, Jennifer; Zaramody, Alphonse; Curtis, Deborah J; Nievergelt, Caroline M; Mundy, Nicholas I
2009-02-05
Hybrid zones generally represent areas of secondary contact after speciation. The nature of the interaction between genes of individuals in a hybrid zone is of interest in the study of evolutionary processes. In this study, data from nuclear microsatellites and mitochondrial DNA sequences were used to genetically characterize hybridization between wild mongoose lemurs (Eulemur mongoz) and brown lemurs (E. fulvus) at Anjamena in west Madagascar. Two segments of mtDNA have been sequenced and 12 microsatellite loci screened in 162 brown lemurs and mongoose lemurs. Among the mongoose lemur population at Anjamena, we identified two F1 hybrids (one also having the mtDNA haplotype of E. fulvus) and six other individuals with putative introgressed alleles in their genotype. Principal component analysis groups both hybrids as intermediate between E. mongoz and E. fulvus and admixture analyses revealed an admixed genotype for both animals. Paternity testing proved one F1 hybrid to be fertile. Of the eight brown lemurs genotyped, all have either putative introgressed microsatellite alleles and/or the mtDNA haplotype of E. mongoz. Introgression is bidirectional for the two species, with an indication that it is more frequent in brown lemurs than in mongoose lemurs. We conclude that this hybridization occurs because mongoose lemurs have expanded their range relatively recently. Introgressive hybridization may play an important role in the unique lemur radiation, as has already been shown in other rapidly evolving animals.
Genetic examination of the putative skull of Jan Kochanowski reveals its female sex
Kupiec, Tomasz; Branicki, Wojciech
2011-01-01
We report the results of genetic examination of the putative skull of Jan Kochanowski (1530-1584), a great Polish renaissance poet. The skull was retrieved in 1791 by historian Tadeusz Czacki from the Kochanowski family tomb and became the property of the Czartoryskis Museum in Krakow. An anthropological study in 1926 questioned its male origin, which raised doubts about its authenticity. Our report presents genetic evidence that resolves this dispute. From the sole tooth we obtained a sufficient amount of DNA to perform the analysis of nuclear markers. The analysis of the sex-informative part of intron 1 in amelogenin, genotyped using AmpFiSTR® NGM PCR Amplification Kit and Powerplex® ESI17 Kit human identification systems, revealed the female origin of the tooth. The female origin was further confirmed by the analysis of a portion of amelogenin intron 2, a microsatellite marker located on the X chromosome, as well as by a lack of signal from Y chromosomal microsatellite markers and the sex-determining region Y marker. Data obtained for two hypervariable regions, HVI and HVII, in mitochondrial DNA showed that mtDNA haplotype was relatively frequent among contemporary Europeans. The analysis of a set of single nucleotide polymorphisms relevant for prediction of the iris color indicated an 87% probability that the woman had hazel or brown eye color. PMID:21674838
Genetic examination of the putative skull of Jan Kochanowski reveals its female sex.
Kupiec, Tomasz; Branicki, Wojciech
2011-06-01
We report the results of genetic examination of the putative skull of Jan Kochanowski (1530-1584), a great Polish renaissance poet. The skull was retrieved in 1791 by historian Tadeusz Czacki from the Kochanowski family tomb and became the property of the Czartoryskis Museum in Krakow. An anthropological study in 1926 questioned its male origin, which raised doubts about its authenticity. Our report presents genetic evidence that resolves this dispute. From the sole tooth we obtained a sufficient amount of DNA to perform the analysis of nuclear markers. The analysis of the sex-informative part of intron 1 in amelogenin, genotyped using AmpFiSTR® NGM PCR Amplification Kit and Powerplex® ESI17 Kit human identification systems, revealed the female origin of the tooth. The female origin was further confirmed by the analysis of a portion of amelogenin intron 2, a microsatellite marker located on the X chromosome, as well as by a lack of signal from Y chromosomal microsatellite markers and the sex-determining region Y marker. Data obtained for two hypervariable regions, HVI and HVII, in mitochondrial DNA showed that mtDNA haplotype was relatively frequent among contemporary Europeans. The analysis of a set of single nucleotide polymorphisms relevant for prediction of the iris color indicated an 87% probability that the woman had hazel or brown eye color.
Prajapati, Surendra K; Joshi, Hema; Carlton, Jane M; Rizvi, M Alam
2013-01-01
The evolutionary history and age of Plasmodium vivax has been inferred as both recent and ancient by several studies, mainly using mitochondrial genome diversity. Here we address the age of P. vivax on the Indian subcontinent using selectively neutral housekeeping genes and tandem repeat loci. Analysis of ten housekeeping genes revealed a substantial number of SNPs (n = 75) from 100 P. vivax isolates collected from five geographical regions of India. Neutrality tests showed a majority of the housekeeping genes were selectively neutral, confirming the suitability of housekeeping genes for inferring the evolutionary history of P. vivax. In addition, a genetic differentiation test using housekeeping gene polymorphism data showed a lack of geographical structuring between the five regions of India. The coalescence analysis of the time to the most recent common ancestor estimate yielded an ancient TMRCA (232,228 to 303,030 years) and long-term population history (79,235 to 104,008) of extant P. vivax on the Indian subcontinent. Analysis of 18 tandem repeat loci polymorphisms showed substantial allelic diversity and heterozygosity per locus, and analysis of potential bottlenecks revealed the signature of a stable P. vivax population, further corroborating our ancient age estimates. For the first time we report a comparable evolutionary history of P. vivax inferred by nuclear genetic markers (putative housekeeping genes) to that inferred from mitochondrial genome diversity.
Rice Ovate Family Protein 2 (OFP2) alters hormonal homeostasis and vasculature development.
Schmitz, Aaron J; Begcy, Kevin; Sarath, Gautam; Walia, Harkamal
2015-12-01
OFP (Ovate Family Protein) is a transcription factor family found only in plants. In dicots, OFPs control fruit shape and secondary cell wall biosynthesis. OFPs are also thought to function through interactions with KNOX and BELL transcription factors. Here, we have functionally characterized OsOFP2, a member of the OFP subgroup associated with regulating fruit shape. OsOFP2 was found to localize to the nucleus and to the cytosol. A putative nuclear export signal was identified within the OVATE domain and was required for the localization of OsOFP2 to distinct cytosolic spots. Rice plants overexpressing OsOFP2 were reduced in height and exhibited altered leaf morphology, seed shape, and positioning of vascular bundles in stems. Transcriptome analysis indicated disruptions of genes associated with vasculature development, lignin biosynthesis, and hormone homeostasis. Reduced expression of the gibberellin biosynthesis gene GA 20-oxidase 7 coincided with lower gibberellin content in OsOFP2 overexpression lines. Also, we found that OsOFP2 was expressed in plant vasculature and determined that putative vascular development KNOX and BELL proteins interact with OsOFP2. KNOX and BELL genes are known to suppress gibberellin biosynthesis through GA20ox gene regulation and can restrict lignin biosynthesis. We propose that OsOFP2 could modulate KNOX-BELL function to control diverse aspects of development including vasculature development. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
King, Gordon; Hill, Justine M.; Martin, Jennifer L.; Mylne, Joshua S.
2009-01-01
VERNALIZATION1 (VRN1) is required in the model plant Arabidopsis thaliana for the epigenetic suppression of the floral repressor FLC by prolonged cold treatment. Stable suppression of FLC accelerates flowering, a physiological process known as vernalization. VRN1 is a 341-residue DNA-binding protein that contains two plant-specific B3 domains (B3a and B3b), a putative nuclear localization sequence (NLS) and two putative PEST domains. VRN1208–341 includes the second B3 domain and a region upstream that is highly conserved in the VRN1 orthologues of other dicotyledonous plants. VRN1208–341 was crystallized by the hanging-drop method in 0.05 M sodium acetate pH 6.0 containing 1.0 M NaCl and 18%(w/v) PEG 3350. Preliminary X-ray diffraction data analysis revealed that the VRN1208–341 crystal diffracted to 2.1 Å and belonged to space group C2, with unit-cell parameters a = 105.2, b = 47.9, c = 61.2 Å, α = 90.0, β = 115.4, γ = 90.0°. Assuming that two molecules occupy the asymmetric unit, a Matthews coefficient of 2.05 Å3 Da−1 and a solvent content of 40.1% were calculated. PMID:19255487
Chen, Zhenchuan; Zhang, Wei; Yun, Zhimin; Zhang, Xue; Gong, Feng; Wang, Yunfang; Ji, Shouping; Leng, Ling
2018-06-01
In response to DNA damage, proliferating cell nuclear antigen (PCNA) has an important role as a positive regulator and as a scaffold protein associated with DNA damage bypass and repair pathways by serving as a platform for the recruitment of associated components. As demonstrated in the present study, the ubiquitin‑like modifier human leukocyte antigen F locus adjacent transcript 10 (FAT10), which binds to PCNA but has not previously been demonstrated to be associated with the DNA damage response (DDR), is induced by ultraviolet/ionizing radiation and VP‑16 treatment in HeLa cells. Furthermore, DNA damage enhances FAT10 expression. Immunoprecipitation analysis suggested PCNA is modified by FAT10, and the degradation of FATylated PCNA located in the cytoplasm is regulated by the 26S proteasome, which is also responsible for the upregulation of nuclear foci formation. Furthermore, immunofluorescence experiment suggested FAT10 co‑localizes with PCNA in nuclear foci, thus suggesting that FATylation of PCNA may affect DDR via the induction of PCNA degradation in the cytoplasm or nucleus. In addition, immunohistochemistry experiment suggested the expression levels of FAT10 and PCNA are enhanced in HCC tissues compared with healthy liver tissues; however, the expression of FAT10 is suppressed in regenerated liver tissues, which express high levels of PCNA, thus suggesting that the association between FAT10 and PCNA expression is only exhibited in tumor tissues. In conclusion, the results of the present study suggest that FAT10 may be involved in DDR and therefore the progression of tumorigenesis.
DOE Office of Scientific and Technical Information (OSTI.GOV)
R. Fink, D. Hill, J. O'Hara
2004-11-30
Nuclear plant operators face a significant challenge designing and modifying control rooms. This report provides guidance on planning, designing, implementing and operating modernized control rooms and digital human-system interfaces.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fukuchi, Mikoto; Wanotayan, Rujira; Liu, Sicheng
2015-06-12
XRCC4 and DNA Ligase IV (LIG4) cooperate to join two DNA ends at the final step of DNA double-strand break (DSB) repair through non-homologous end-joining (NHEJ). However, it is not fully understood how these proteins are localized to the nucleus. Here we created XRCC4{sup K271R} mutant, as Lys271 lies within the putative nuclear localization signal (NLS), and XRCC4{sup K210R} mutant, as Lys210 was reported to undergo SUMOylation, implicated in the nuclear localization of XRCC4. Wild-type and mutated XRCC4 with EGFP tag were introduced into HeLa cell, in which endogenous XRCC4 had been knocked down using siRNA directed to 3′-untranslated region,more » and tested for the nuclear localization function by fluorescence microscopy. XRCC4{sup K271R} was defective in the nuclear localization of itself and LIG4, whereas XRCC4{sup K210R} was competent for the nuclear localization with LIG4. To examine DSB repair function, wild-type and mutated XRCC4 were introduced into XRCC4-deficient M10. M10-XRCC4{sup K271R}, but not M10-XRCC4{sup K210R}, showed significantly reduced surviving fraction after 2 Gy γ-ray irradiation as compared to M10-XRCC4{sup WT}. The number of γ-H2AX foci remaining 2 h after 2 Gy γ-ray irradiation was significantly greater in M10-XRCC4{sup K271R} than in M10-XRCC4{sup WT}, whereas it was only marginally increased in M10-XRCC4{sup K210R} as compared to M10-XRCC4{sup WT}. The present results collectively indicated that Lys271, but not Lys210, of XRCC4 is required for the nuclear localization of XRCC4 and LIG4 and that the nuclear localizing ability is essential for DSB repair function of XRCC4. - Highlights: • XRCC4{sup K271R} is defective in the nuclear localization of itself and LIG4. • XRCC4{sup K210R} is competent for the nuclear localization of itself and LIG4. • XRCC4{sup K271R} is deficient in DSB repair function. • XRCC4{sup K210R} is mostly normal in DSB repair function.« less
Guzmán-Guzmán, Paulina; Alemán-Duarte, Mario Iván; Delaye, Luis; Herrera-Estrella, Alfredo; Olmedo-Monfil, Vianey
2017-02-15
Trichoderma spp. can establish beneficial interactions with plants by promoting plant growth and defense systems, as well as, antagonizing fungal phytopathogens in mycoparasitic interactions. Such interactions depend on signal exchange between both participants and can be mediated by effector proteins that alter the host cell structure and function, allowing the establishment of the relationship. The main purpose of this work was to identify, using computational methods, candidates of effector proteins from T. virens, T. atroviride and T. reesei, validate the expression of some of the genes during a beneficial interaction and mycoparasitism and to define the biological function for one of them. We defined a catalogue of putative effector proteins from T. virens, T. atroviride and T. reesei. We further validated the expression of 16 genes encoding putative effector proteins from T. virens and T. atroviride during the interaction with the plant Arabidopsis thaliana, and with two anastomosis groups of the phytopathogenic fungus Rhizoctonia solani. We found genes which transcript levels are modified in response to the presence of both plant fungi, as well as genes that respond only to either a plant or a fungal host. Further, we show that overexpression of the gene tvhydii1, a Class II hydrophobin family member, enhances the antagonistic activity of T. virens against R. solani AG2. Further, deletion of tvhydii1 results in reduced colonization of plant roots, while its overexpression increases it. Our results show that Trichoderma is able to respond in different ways to the presence of a plant or a fungal host, and it can even distinguish between different strains of fungi of a given species. The putative effector proteins identified here may play roles in preventing perception of the fungus by its hosts, favoring host colonization or protecting it from the host's defense response. Finally, the novel effector protein TVHYDII1 plays a role in plant root colonization by T, virens, and participates in its antagonistic activity against R. solani.
Daphnia HR96 is a Promiscuous Xenobiotic and Endobiotic Nuclear Receptor
Karimullina, Elina; Li, Yangchun; Ginjupalli, Gautam; Baldwin, William S.
2012-01-01
Daphnia pulex is the first crustacean to have its genome sequenced. The genome project provides new insight and data into how an aquatic crustacean may respond to environmental stressors, including toxicants. We cloned Daphnia pulex HR96 (DappuHR96), a nuclear receptor orthologous to the CAR/PXR/VDR group of nuclear receptors. In Drosophila melanogaster, (hormone receptor 96) HR96 responds to phenobarbital exposure and has been hypothesized as a toxicant receptor. Therefore, we set up a transactivation assay to test whether DappuHR96 is a promiscuous receptor activated by xenobiotics and endobiotics similar to the constitutive androstane receptor (CAR) and the pregnane X-receptor (PXR). Transactivation assays performed with a GAL4-HR96 chimera demonstrate that HR96 is a promiscuous toxicant receptor activated by a diverse set of chemicals such as pesticides, hormones, and fatty acids. Several environmental toxicants activate HR96 including estradiol, pyriproxyfen, chlorpyrifos, atrazine, and methane arsonate. We also observed repression of HR96 activity by chemicals such as triclosan, androstanol, and fluoxetine. Nearly 50% of the chemicals tested activated or inhibited HR96. Interestingly, unsaturated fatty acids were common activators or inhibitors of HR96 activity, indicating a link between diet and toxicant response. The omega-6 and omega-9 unsaturated fatty acids linoleic and oleic acid activated HR96, but the omega-3 unsaturated fatty acids alpha-linolenic acid and docosahexaenoic acid inhibited HR96, suggesting that these two distinct sets of lipids perform opposing roles in Daphnia physiology. This also provides a putative mechanism by which the ratio of dietary unsaturated fats may affect the ability of an organism to respond to a toxic insult. In summary, HR96 is a promiscuous nuclear receptor activated by numerous endo- and xenobiotics. PMID:22466357
Rabiee, Atefeh; Schwämmle, Veit; Sidoli, Simone; Dai, Jie; Rogowska-Wrzesinska, Adelina; Mandrup, Susanne; Jensen, Ole N
2017-03-01
Adipocytes (fat cells) are important endocrine and metabolic cells critical for systemic insulin sensitivity. Both adipose excess and insufficiency are associated with adverse metabolic function. Adipogenesis is the process whereby preadipocyte precursor cells differentiate into lipid-laden mature adipocytes. This process is driven by a network of transcriptional regulators (TRs). We hypothesized that protein PTMs, in particular phosphorylation, play a major role in activating and propagating signals within TR networks upon induction of adipogenesis by extracellular stimulus. We applied MS-based quantitative proteomics and phosphoproteomics to monitor the alteration of nuclear proteins during the early stages (4 h) of preadipocyte differentiation. We identified a total of 4072 proteins including 2434 phosphorylated proteins, a majority of which were assigned as regulators of gene expression. Our results demonstrate that adipogenic stimuli increase the nuclear abundance and/or the phosphorylation levels of proteins involved in gene expression, cell organization, and oxidation-reduction pathways. Furthermore, proteins acting as negative modulators involved in negative regulation of gene expression, insulin stimulated glucose uptake, and cytoskeletal organization showed a decrease in their nuclear abundance and/or phosphorylation levels during the first 4 h of adipogenesis. Among 288 identified TRs, 49 were regulated within 4 h of adipogenic stimulation including several known and many novel potential adipogenic regulators. We created a kinase-substrate database for 3T3-L1 preadipocytes by investigating the relationship between protein kinases and protein phosphorylation sites identified in our dataset. A majority of the putative protein kinases belong to the cyclin-dependent kinase family and the mitogen-activated protein kinase family including P38 and c-Jun N-terminal kinases, suggesting that these kinases act as orchestrators of early adipogenesis. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
The HELLAS2XMM survey. XI. Unveiling the nature of X-ray bright optically normal galaxies
NASA Astrophysics Data System (ADS)
Civano, F.; Mignoli, M.; Comastri, A.; Vignali, C.; Fiore, F.; Pozzetti, L.; Brusa, M.; La Franca, F.; Matt, G.; Puccetti, S.; Cocchia, F.
2007-12-01
Aims:X-ray bright optically normal galaxies (XBONGs) constitute a small but significant fraction of hard X-ray selected sources in recent Chandra and XMM-Newton surveys. Even though several possibilities were proposed to explain why a relatively luminous hard X-ray source does not leave any significant signature of its presence in terms of optical emission lines, the nature of XBONGs is still subject of debate. We aim to better understand their nature by means of a multiwavelength and morphological analysis of a small sample of these sources. Methods: Good-quality photometric near-infrared data (ISAAC/VLT) of four low-redshift (z = 0.1{-}0.3) XBONGs, selected from the HELLAS2XMM survey, have been used to search for the presence of the putative nucleus, applying the surface-brightness decomposition technique through the least-squares fitting program GALFIT. Results: The surface brightness decomposition allows us to reveal a nuclear point-like source, likely to be responsible for the X-ray emission, in two out of the four sources. The results indicate that moderate amounts of gas and dust, covering a large solid angle (possibly 4π) at the nuclear source, combined with the low nuclear activity, may explain the lack of optical emission lines. The third XBONG is associated with an X-ray extended source and no nuclear excess is detected in the near infrared at the limits of our observations. The last source is associated to a close (d≤ 1 arcsec) double system and the fitting procedure cannot achieve a firm conclusion. Based on observations made at the European Southern Observatory, Paranal, Chile (ESO Programme ID 69.A-0554).
Zang, Aiping; Xu, Xiaojie; Neill, Steven; Cai, Weiming
2010-01-01
Nucleo-cytoplasmic partitioning of regulatory proteins is increasingly being recognized as a major control mechanism for the regulation of signalling in plants. Ras-related nuclear protein (Ran) GTPase is required for regulating transport of proteins and RNA across the nuclear envelope and also has roles in mitotic spindle assembly and nuclear envelope (NE) assembly. However, thus far little is known of any Ran functions in the signalling pathways in plants in response to changing environmental stimuli. The OsRAN2 gene, which has high homology (77% at the amino acid level) with its human counterpart, was isolated here. Subcellular localization results showed that OsRan2 is mainly localized in the nucleus, with some in the cytoplasm. Transcription of OsRAN2 was reduced by salt, osmotic, and exogenous abscisic acid (ABA) treatments, as determined by real-time PCR. Overexpression of OsRAN2 in rice resulted in enhanced sensitivity to salinity, osmotic stress, and ABA. Seedlings of transgenic Arabidopsis thaliana plants overexpressing OsRAN2 were overly sensitive to salinity stress and exogenous ABA treatment. Furthermore, three ABA- or stress-responsive genes, AtNCED3, AtPLC1, and AtMYB2, encoding a key enzyme in ABA synthesis, a phospholipase C homologue, and a putative transcriptional factor, respectively, were shown to have differentially induced expression under salinity and ABA treatments in transgenic and wild-type Arabidopsis plants. OsRAN2 overexpression in tobacco epidermal leaf cells disturbed the nuclear import of a maize (Zea mays L.) leaf colour transcription factor (Lc). In addition, gene-silenced rice plants generated via RNA interference (RNAi) displayed pleiotropic developmental abnormalities and were male sterile. PMID:20018899
The deubiquitinating enzyme DUBAI stabilizes DIAP1 to suppress Drosophila apoptosis
Yang, C-S; Sinenko, S A; Thomenius, M J; Robeson, A C; Freel, C D; Horn, S R; Kornbluth, S
2014-01-01
Deubiquitinating enzymes (DUBs) counteract ubiquitin ligases to modulate the ubiquitination and stability of target signaling molecules. In Drosophila, the ubiquitin–proteasome system has a key role in the regulation of apoptosis, most notably, by controlling the abundance of the central apoptotic regulator DIAP1. Although the mechanism underlying DIAP1 ubiquitination has been extensively studied, the precise role of DUB(s) in controlling DIAP1 activity has not been fully investigated. Here we report the identification of a DIAP1-directed DUB using two complementary approaches. First, a panel of putative Drosophila DUBs was expressed in S2 cells to determine whether DIAP1 could be stabilized, despite treatment with death-inducing stimuli that would induce DIAP1 degradation. In addition, RNAi fly lines were used to detect modifiers of DIAP1 antagonist-induced cell death in the developing eye. Together, these approaches identified a previously uncharacterized protein encoded by CG8830, which we named DeUBiquitinating-Apoptotic-Inhibitor (DUBAI), as a novel DUB capable of preserving DIAP1 to dampen Drosophila apoptosis. DUBAI interacts with DIAP1 in S2 cells, and the putative active site of its DUB domain (C367) is required to rescue DIAP1 levels following apoptotic stimuli. DUBAI, therefore, represents a novel locus of apoptotic regulation in Drosophila, antagonizing cell death signals that would otherwise result in DIAP1 degradation. PMID:24362437
Zeng, Nina; D'Souza, Randall F; Sorrenson, Brie; Merry, Troy L; Barnett, Matthew P G; Mitchell, Cameron J; Cameron-Smith, David
2018-06-01
Dietary protein and resistance exercise (RE) are both potent stimuli of the mammalian target of rapamycin complex 1 (mTORC1). Sestrins1, 2, 3 are multifunctional proteins that regulate mTORC1, stimulate autophagy and alleviate oxidative stress. Of this family, Sestrin2 is a putative leucine sensor implicated in mTORC1 and AMP-dependent protein kinase (AMPK) regulation. There is currently no data examining the responsiveness of Sestrin2 to dietary protein ingestion, with or without RE. In Study 1, 16 males ingested either 10 or 20 g of milk protein concentrate (MPC) with muscle biopsies collected pre, 90 and 210 min post-beverage consumption. In Study 2, 20 males performed a bout of RE immediately followed by the consumption of 9 g of MPC or carbohydrate placebo. Analysis of Sestrins, AMPK and antioxidant responses was examined. Dietary protein ingestion did not result in Sestrin2 mobility shift. After RE, Sestrin2 phosphorylation state was significantly altered and was not further modified by post-exercise protein or carbohydrate ingestion. With RE, AMPK phosphorylation remained stable, while the mRNA expressions of several antioxidants were upregulated. Dietary protein ingestion did not affect the signalling by the family of Sestrins. With RE, Sestrin2 was hyperphosphorylated, with no further evidence of a relationship to AMPK signalling.
Estimating hybridization in the presence of coalescence using phylogenetic intraspecific sampling.
Gerard, David; Gibbs, H Lisle; Kubatko, Laura
2011-10-06
A well-known characteristic of multi-locus data is that each locus has its own phylogenetic history which may differ substantially from the overall phylogenetic history of the species. Although the possibility that this arises through incomplete lineage sorting is often incorporated in models for the species-level phylogeny, it is much less common for hybridization to also be formally included in such models. We have modified the evolutionary model of Meng and Kubatko (2009) to incorporate intraspecific sampling of multiple individuals for estimation of speciation times and times of hybridization events for testing for hybridization in the presence of incomplete lineage sorting. We have also utilized a more efficient algorithm for obtaining our estimates. Using simulations, we demonstrate that our approach performs well under conditions motivated by an empirical data set for Sistrurus rattlesnakes where putative hybridization has occurred. We further demonstrate that the method is able to accurately detect the signature of hybridization in the data, while this signal may be obscured when other species-tree inference methods that ignore hybridization are used. Our approach is shown to be powerful in detecting hybridization when it is present. When applied to the Sistrurus data, we find no evidence of hybridization; instead, it appears that putative hybrid snakes in Missouri are most likely pure S. catenatus tergeminus in origin, which has significant conservation implications.
Morra, Joshua T; Glick, Stanley D; Cheer, Joseph F
2012-09-01
Patients suffering from amphetamine-induced psychosis display repetitive behaviors, partially alleviated by antipsychotics, which are reminiscent of rodent stereotypies. Due to recent evidence implicating endocannabinoid involvement in brain disorders, including psychosis, we studied the effects of endocannabinoid signaling on neuronal oscillations of rats exhibiting methamphetamine stereotypy. Neuronal network oscillations were recorded with multiple single electrode arrays aimed at the nucleus accumbens of freely-moving rats. During the experiments, animals were dosed intravenously with the CB1 receptor antagonist rimonabant (0.3 mg/kg) or vehicle followed by an ascending dose regimen of methamphetamine (0.01, 0.1, 1, and 3 mg/kg; cumulative dosing). The effects of drug administration on stereotypy and local gamma oscillations were evaluated. Methamphetamine treatment significantly increased high frequency gamma oscillations (∼80 Hz). Entrainment of a subpopulation of nucleus accumbens neurons to high frequency gamma was associated with stereotypy encoding in putative fast-spiking interneurons, but not in putative medium spiny neurons. The observed ability of methamphetamine to induce both stereotypy and high frequency gamma power was potently disrupted following CB1 receptor blockade. The present data suggest that CB1 receptor-dependent mechanisms are recruited by methamphetamine to modify striatal interneuron oscillations that accompany changes in psychomotor state, further supporting the link between endocannabinoids and schizophrenia spectrum disorders. Copyright © 2012 Elsevier Ltd. All rights reserved.
Shape-shifting corals: Molecular markers show morphology is evolutionarily plastic in Porites
Forsman, Zac H; Barshis, Daniel J; Hunter, Cynthia L; Toonen, Robert J
2009-01-01
Background Corals are notoriously difficult to identify at the species-level due to few diagnostic characters and variable skeletal morphology. This 'coral species problem' is an impediment to understanding the evolution and biodiversity of this important and threatened group of organisms. We examined the evolution of the nuclear ribosomal internal transcribed spacer (ITS) and mitochondrial markers (COI, putative control region) in Porites, one of the most taxonomically challenging and ecologically important genera of reef-building corals. Results Nuclear and mitochondrial markers were congruent, clearly resolving many traditionally recognized species; however, branching and mounding varieties were genetically indistinguishable within at least two clades, and specimens matching the description of 'Porites lutea' sorted into three genetically divergent groups. Corallite-level features were generally concordant with genetic groups, although hyper-variability in one group (Clade I) overlapped and obscured several others, and Synarea (previously thought to be a separate subgenus) was closely related to congeners despite its unique morphology. Scanning electron microscopy revealed subtle differences between genetic groups that may have been overlooked previously as taxonomic characters. Conclusion This study demonstrates that the coral skeleton can be remarkably evolutionarily plastic, which may explain some taxonomic difficulties, and obscure underlying patterns of endemism and diversity. PMID:19239678
NASA Astrophysics Data System (ADS)
Budnitz, Robert J.
2011-11-01
The 104 nuclear plants operating in the US today are far safer than they were 20-30 years ago. For example, there's been about a 100-fold reduction in the occurrence of "significant events" since the late 1970s. Although the youngest of currently operating US plants was designed in the 1970s, all have been significantly modified over the years. Key contributors to the safety gains are a vigilant culture, much improved equipment reliability, greatly improved training of operators and maintenance workers, worldwide sharing of experience, and the effective use of probabilistic risk assessment. Several manufacturers have submitted high quality new designs for large reactors to the U.S. Nuclear Regulatory Commission (NRC) for design approval, and some designers are taking a second look at the economies of smaller, modular reactors.
Effects of medium on nuclear properties in multifragmentation
NASA Astrophysics Data System (ADS)
De, J. N.; Samaddar, S. K.; Viñas, X.; Centelles, M.; Mishustin, I. N.; Greiner, W.
2012-08-01
In multifragmentation of hot nuclear matter, properties of fragments embedded in a soup of nucleonic gas and other fragments should be modified as compared with isolated nuclei. Such modifications are studied within a simple model where only nucleons and one kind of heavy nuclei are considered. The interaction between different species is described with a momentum-dependent two-body potential whose parameters are fitted to reproduce properties of cold isolated nuclei. The internal energy of heavy fragments is parametrized according to a liquid-drop model with density- and temperature-dependent parameters. Calculations are carried out for several subnuclear densities and moderate temperatures, for isospin-symmetric and asymmetric systems. We find that the fragments get stretched due to interactions with the medium and their binding energies decrease with increasing temperature and density of nuclear matter.
Experimental evidence supports a sex-specific selective sieve in mitochondrial genome evolution.
Innocenti, Paolo; Morrow, Edward H; Dowling, Damian K
2011-05-13
Mitochondria are maternally transmitted; hence, their genome can only make a direct and adaptive response to selection through females, whereas males represent an evolutionary dead end. In theory, this creates a sex-specific selective sieve, enabling deleterious mutations to accumulate in mitochondrial genomes if they exert male-specific effects. We tested this hypothesis, expressing five mitochondrial variants alongside a standard nuclear genome in Drosophila melanogaster, and found striking sexual asymmetry in patterns of nuclear gene expression. Mitochondrial polymorphism had few effects on nuclear gene expression in females but major effects in males, modifying nearly 10% of transcripts. These were mostly male-biased in expression, with enrichment hotspots in the testes and accessory glands. Our results suggest an evolutionary mechanism that results in mitochondrial genomes harboring male-specific mutation loads.
PERFORMANCE OF TWO LIQUID METAL TURBOPROP ENGINES UTILIZING A CIRCULATING FUEL REACTOR
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tiedemann, H.J.; Mathews, L.
1955-01-20
The performance of two all-nuclear turboprop engines utilizing the circulating fuel reactor with a fluoride fuel temperature of I500 deg F was investigated. Data are presented for off-match-point and modified match-point performances. Results are given in graph form. (M.C.G.)
Effect of different catalysts on urea-formaldehyde resin synthesis
Qi-Ning Sun; Chung-Yun Hse; Todd F. Shupe
2014-01-01
Four catalysts (H2SO4, HCl, H3PO4, and NaOH/NH4OH) were studied in the preparation of melamine modified ureaâ formaldehyde (UFM) resins. 13C-nuclear magnetic resonance spectroscopic analysis of the UFM resins at different synthesis stages revealed the...
Brenman, J E; Gao, F B; Jan, L Y; Jan, Y N
2001-11-01
Morphological complexity of neurons contributes to their functional complexity. How neurons generate different dendritic patterns is not known. We identified the sequoia mutant from a previous screen for dendrite mutants. Here we report that Sequoia is a pan-neural nuclear protein containing two putative zinc fingers homologous to the DNA binding domain of Tramtrack. sequoia mutants affect the cell fate decision of a small subset of neurons but have global effects on axon and dendrite morphologies of most and possibly all neurons. In support of sequoia as a specific regulator of neuronal morphogenesis, microarray experiments indicate that sequoia may regulate downstream genes that are important for executing neurite development rather than altering a variety of molecules that specify cell fates.
Ouedraogo, Zangbéwendé Guy; Fouache, Allan; Trousson, Amalia; Baron, Silvère; Lobaccaro, Jean-Marc A
2017-10-01
Liver X receptors (LXRs) are members of the nuclear receptor superfamily that have been shown to regulate various physiological functions such as lipid metabolism and cholesterol homeostasis. Concordant reports have elicited the possibility to target them to cure many human diseases including arteriosclerosis, cancer, arthritis, and diabetes. The high relevance of modulating LXR activities to treat numerous skin diseases, mainly those with exacerbated inflammation processes, contrasts with the lack of approved therapeutic use. This review makes an assessment to sum up the findings regarding the physiological roles of LXRs in skin and help progress towards the therapeutic and safe management of their activities. It focuses on the possible pharmacological targeting of LXRs to cure or prevent selected skin diseases. Copyright © 2017 Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Unterberger, Claudia; Hanson, Steven; Department of Infection, Immunity and Inflammation, University of Leicester, University Road, Leicester LE1 9HN
Little is known about determinants regulating expression of Mannan-binding lectin associated serine protease-2 (MASP-2), the effector component of the lectin pathway of complement activation. Comparative bioinformatic analysis of the MASP2 promoter regions in human, mouse, and rat, revealed conservation of two putative Stat binding sites, termed StatA and StatB. Site directed mutagenesis specific for these sites was performed. Transcription activity was decreased 5-fold when StatB site was mutated in the wildtype reporter gene construct. Gel retardation and competition assays demonstrated that proteins contained in the nuclear extract prepared from HepG2 specifically bound double-stranded StatB oligonucleotides. Supershift analysis revealed Stat3 tomore » be the major specific binding protein. We conclude that Stat3 binding is important for MASP2 promoter activity.« less
Distribution and population genetics of walleye and sauger
Haponski, Amanda E.; Sloss, Brian L.
2014-01-01
Conserving genetic diversity and local adaptations are management priorities for wild populations of exploited species, which increasingly are subject to climate change, habitat loss, and pollution. These constitute growing concerns for the walleye Sander vitreus, an ecologically and economically valuable North American temperate fish with large Laurentian Great Lakes' fisheries. This study compares genetic diversity and divergence patterns across its widespread native range using mitochondrial (mt) DNA control region sequences and nine nuclear DNA microsatellite (μsat) loci, examining historic and contemporary influences. We analyze the genetic and morphological characters of a putative endemic variant– “blue pike” S. v. “glaucus” –described from Lakes Erie and Ontario, which became extinct. Walleye with turquoise-colored mucus also are evaluated, since some have questioned whether these are related to the “blue pike”.
Souquere, Sylvie; Weil, Dominique; Pierron, Gérard
2015-01-01
In order to gain insights on the nuclear organization in mammalian cells, we characterized ultrastructurally nuclear bodies (NBs) previously described as fluorescent foci. Using high resolution immunoelectron microscopy (I-EM), we provide evidence that CNoBs (CRM1-Nucleolar bodies) and INBs (Intranucleolar bodies) are distinct genuine nucleolar structures in untreated HeLa cells. INBs are fibrillar and concentrate the post-translational modifiers SUMO1 and SUMO-2/3 as strongly as PML bodies. In contrast, the smallest CRM1-labeled CNoBs are vitreous, preferentially located at the periphery of the nucleolus and, intricately linked to the chromatin network. Upon blockage of the CRM1-dependent nuclear export by leptomycin B (LMB), CNoBs disappear while p62/SQSTM1-containing fibrillar nuclear bodies are induced. These p62 bodies are enriched in ubiquitinated proteins. They progressively associate with PML bodies to form hybrid bodies of which PML decorates the periphery while p62/SQSTM1 is centrally-located. Our study is expanding the repertoire of nuclear bodies; revealing a previously unrecognized composite nucleolar landscape and a new mode of interactions between ubiquitous (PML) and stress-induced (p62) nuclear bodies, resulting in the formation of hybrid bodies. PMID:26275159
Nuclear organization mediates cancer-compromised genetic and epigenetic control.
Zaidi, Sayyed K; Fritz, Andrew; Tracy, Kirsten; Gordon, Jonathan; Tye, Coralee; Boyd, Joseph; Van Wijnen, Andre; Nickerson, Jeffrey; Imbalzano, Anthony; Lian, Jane; Stein, Janet; Stein, Gary
2018-05-09
Nuclear organization is functionally linked to genetic and epigenetic regulation of gene expression for biological control and is modified in cancer. Nuclear organization supports cell growth and phenotypic properties of normal and cancer cells by facilitating physiologically responsive interactions of chromosomes, genes and regulatory complexes at dynamic three-dimensional microenvironments. We will review nuclear structure/function relationships that include: 1. Epigenetic bookmarking of genes by phenotypic transcription factors to control fidelity and plasticity of gene expression as cells enter and exit mitosis; 2. Contributions of chromatin remodeling to breast cancer nuclear morphology, metabolism and effectiveness of chemotherapy; 3. Relationships between fidelity of nuclear organization and metastasis of breast cancer to bone; 4. Dynamic modifications of higher-order inter- and intra-chromosomal interactions in breast cancer cells; 5. Coordinate control of cell growth and phenotype by tissue-specific transcription factors; 6. Oncofetal epigenetic control by bivalent histone modifications that are functionally related to sustaining the stem cell phenotype; and 7. Noncoding RNA-mediated regulation in the onset and progression of breast cancer. The discovery of components to nuclear organization that are functionally related to cancer and compromise gene expression have the potential for translation to innovative cancer diagnosis and targeted therapy. Copyright © 2018 Elsevier Ltd. All rights reserved.
Novotný, Jan Philipp; Chughtai, Ahmed Ali; Kostrouchová, Markéta; Kostrouchová, Veronika; Kostrouch, David; Kaššák, Filip; Kaňa, Radek; Schierwater, Bernd; Kostrouchová, Marta
2017-01-01
Trichoplax adhaerens, the only known species of Placozoa is likely to be closely related to an early metazoan that preceded branching of Cnidaria and Bilateria. This animal species is surprisingly well adapted to free life in the World Ocean inhabiting tidal costal zones of oceans and seas with warm to moderate temperatures and shallow waters. The genome of T. adhaerens (sp. Grell) includes four nuclear receptors, namely orthologue of RXR (NR2B), HNF4 (NR2A), COUP-TF (NR2F) and ERR (NR3B) that show a high degree of similarity with human orthologues. In the case of RXR, the sequence identity to human RXR alpha reaches 81% in the DNA binding domain and 70% in the ligand binding domain. We show that T. adhaerens RXR (TaRXR) binds 9-cis retinoic acid (9-cis-RA) with high affinity, as well as high specificity and that exposure of T. adhaerens to 9-cis-RA regulates the expression of the putative T. adhaerens orthologue of vertebrate L-malate-NADP+ oxidoreductase (EC 1.1.1.40) which in vertebrates is regulated by a heterodimer of RXR and thyroid hormone receptor. Treatment by 9-cis-RA alters the relative expression profile of T. adhaerens nuclear receptors, suggesting the existence of natural ligands. Keeping with this, algal food composition has a profound effect on T. adhaerens growth and appearance. We show that nanomolar concentrations of 9-cis-RA interfere with T. adhaerens growth response to specific algal food and causes growth arrest. Our results uncover an endocrine-like network of nuclear receptors sensitive to 9-cis-RA in T. adhaerens and support the existence of a ligand-sensitive network of nuclear receptors at the base of metazoan evolution. PMID:28975052
Garcia-Lor, Andres; Curk, Franck; Snoussi-Trifa, Hager; Morillon, Raphael; Ancillo, Gema; Luro, François; Navarro, Luis; Ollitrault, Patrick
2013-01-01
Background and Aims Despite differences in morphology, the genera representing ‘true citrus fruit trees’ are sexually compatible, and their phylogenetic relationships remain unclear. Most of the important commercial ‘species’ of Citrus are believed to be of interspecific origin. By studying polymorphisms of 27 nuclear genes, the average molecular differentiation between species was estimated and some phylogenetic relationships between ‘true citrus fruit trees’ were clarified. Methods Sanger sequencing of PCR-amplified fragments from 18 genes involved in metabolite biosynthesis pathways and nine putative genes for salt tolerance was performed for 45 genotypes of Citrus and relatives of Citrus to mine single nucleotide polymorphisms (SNPs) and indel polymorphisms. Fifty nuclear simple sequence repeats (SSRs) were also analysed. Key Results A total of 16 238 kb of DNA was sequenced for each genotype, and 1097 single nucleotide polymorphisms (SNPs) and 50 indels were identified. These polymorphisms were more valuable than SSRs for inter-taxon differentiation. Nuclear phylogenetic analysis revealed that Citrus reticulata and Fortunella form a cluster that is differentiated from the clade that includes three other basic taxa of cultivated citrus (C. maxima, C. medica and C. micrantha). These results confirm the taxonomic subdivision between the subgenera Metacitrus and Archicitrus. A few genes displayed positive selection patterns within or between species, but most of them displayed neutral patterns. The phylogenetic inheritance patterns of the analysed genes were inferred for commercial Citrus spp. Conclusions Numerous molecular polymorphisms (SNPs and indels), which are potentially useful for the analysis of interspecific genetic structures, have been identified. The nuclear phylogenetic network for Citrus and its sexually compatible relatives was consistent with the geographical origins of these genera. The positive selection observed for a few genes will help further works to analyse the molecular basis of the variability of the associated traits. This study presents new insights into the origin of C. sinensis. PMID:23104641
Garcia-Lor, Andres; Curk, Franck; Snoussi-Trifa, Hager; Morillon, Raphael; Ancillo, Gema; Luro, François; Navarro, Luis; Ollitrault, Patrick
2013-01-01
Despite differences in morphology, the genera representing 'true citrus fruit trees' are sexually compatible, and their phylogenetic relationships remain unclear. Most of the important commercial 'species' of Citrus are believed to be of interspecific origin. By studying polymorphisms of 27 nuclear genes, the average molecular differentiation between species was estimated and some phylogenetic relationships between 'true citrus fruit trees' were clarified. Sanger sequencing of PCR-amplified fragments from 18 genes involved in metabolite biosynthesis pathways and nine putative genes for salt tolerance was performed for 45 genotypes of Citrus and relatives of Citrus to mine single nucleotide polymorphisms (SNPs) and indel polymorphisms. Fifty nuclear simple sequence repeats (SSRs) were also analysed. A total of 16 238 kb of DNA was sequenced for each genotype, and 1097 single nucleotide polymorphisms (SNPs) and 50 indels were identified. These polymorphisms were more valuable than SSRs for inter-taxon differentiation. Nuclear phylogenetic analysis revealed that Citrus reticulata and Fortunella form a cluster that is differentiated from the clade that includes three other basic taxa of cultivated citrus (C. maxima, C. medica and C. micrantha). These results confirm the taxonomic subdivision between the subgenera Metacitrus and Archicitrus. A few genes displayed positive selection patterns within or between species, but most of them displayed neutral patterns. The phylogenetic inheritance patterns of the analysed genes were inferred for commercial Citrus spp. Numerous molecular polymorphisms (SNPs and indels), which are potentially useful for the analysis of interspecific genetic structures, have been identified. The nuclear phylogenetic network for Citrus and its sexually compatible relatives was consistent with the geographical origins of these genera. The positive selection observed for a few genes will help further works to analyse the molecular basis of the variability of the associated traits. This study presents new insights into the origin of C. sinensis.
A Nuclear Attack on Traumatic Brain Injury: Sequestration of Cell Death in the Nucleus.
Tajiri, Naoki; De La Peña, Ike; Acosta, Sandra A; Kaneko, Yuji; Tamir, Sharon; Landesman, Yosef; Carlson, Robert; Shacham, Sharon; Borlongan, Cesar V
2016-04-01
Exportin 1 (XPO1/CRM1) plays prominent roles in the regulation of nuclear protein export. Selective inhibitors of nuclear export (SINE) are small orally bioavailable molecules that serve as drug-like inhibitors of XPO1, with potent anti-cancer properties. Traumatic brain injury (TBI) presents with a secondary cell death characterized by neuroinflammation that is putatively regulated by nuclear receptors. Here, we report that the SINE compounds (KPT-350 or KPT-335) sequestered TBI-induced neuroinflammation-related proteins (NF-(k)B, AKT, FOXP1) within the nucleus of cultured primary rat cortical neurons, which coincided with protection against TNF-α (20 ng/mL)-induced neurotoxicity as shown by at least 50% and 100% increments in preservation of cell viability and cellular enzymatic activity, respectively, compared to non-treated neuronal cells (P's < 0.05). In parallel, using an in vivo controlled cortical impact (CCI) model of TBI, we demonstrate that adult Sprague-Dawley rats treated post-injury with SINE compounds exhibited significant reductions in TBI-induced behavioral and histological deficits. Animals that received KPT-350 orally starting at 2 h post-TBI and once a day thereafter over the next 4 days exhibited significantly better motor coordination, and balance in the rotorod test and motor asymmetry test by 100-200% improvements, as early as 4 h after initial SINE compound injection that was sustained during subsequent KPT-350 dosing, and throughout the 18-day post-TBI study period compared to vehicle treatment (P's < 0.05). Moreover, KPT-350 reduced cortical core impact area and peri-impact cell death compared to vehicle treatment (P's < 0.05). Both in vitro and in vivo experiments revealed that KPT-350 increased XPO1, AKT, and FOXP1 nuclear expression and relegated NF-(k)B expression within the neuronal nuclei. Altogether, these findings advance the utility of SINE compounds to stop trafficking of cell death proteins within the nucleus as an efficacious treatment for TBI. © 2016 John Wiley & Sons Ltd.
Shackleford, Gregory M; Ganguly, Amit; MacArthur, Craig A
2001-01-01
Background Studies suggest that the related proteins nucleoplasmin and nucleophosmin (also called B23, NO38 or numatrin) are nuclear chaperones that mediate the assembly of nucleosomes and ribosomes, respectively, and that these activities are accomplished through the binding of basic proteins via their acidic domains. Recently discovered and less well characterized members of this family of acidic phosphoproteins include mouse nucleophosmin/nucleoplasmin 3 (Npm3) and Xenopus NO29. Here we report the cloning and initial characterization of the human ortholog of Npm3. Results Human genomic and cDNA clones of NPM3 were isolated and sequenced. NPM3 lies 5.5 kb upstream of FGF8 and thus maps to chromosome 10q24-26. In addition to amino acid similarities, NPM3 shares many physical characteristics with the nucleophosmin/nucleoplasmin family, including an acidic domain, multiple potential phosphorylation sites and a putative nuclear localization signal. Comparative analyses of 14 members of this family from various metazoans suggest that Xenopus NO29 is a candidate ortholog of human and mouse NPM3, and they further group both proteins closer with the nucleoplasmins than with the nucleophosmins. Northern blot analysis revealed that NPM3 was strongly expressed in all 16 human tissues examined, with especially robust expression in pancreas and testis; lung displayed the lowest level of expression. An analysis of subcellular fractions of NIH3T3 cells expressing epitope-tagged NPM3 revealed that NPM3 protein was localized solely in the nucleus. Conclusions Human NPM3 is an abundant and widely expressed protein with primarily nuclear localization. These biological activities, together with its physical relationship to the chaparones nucleoplasmin and nucleophosmin, are consistent with the proposed function of NPM3 as a molecular chaperone functioning in the nucleus. PMID:11722795
Fast REDOR with CPMG multiple-echo acquisition
NASA Astrophysics Data System (ADS)
Hung, Ivan; Gan, Zhehong
2014-01-01
Rotational-Echo Double Resonance (REDOR) is a widely used experiment for distance measurements in solids. The conventional REDOR experiment measures the signal dephasing from hetero-nuclear recoupling under magic-angle spinning (MAS) in a point by point manner. A modified Carr-Purcell Meiboom-Gill (CPMG) multiple-echo scheme is introduced for fast REDOR measurement. REDOR curves are measured from the CPMG echo amplitude modulation under dipolar recoupling. The real time CPMG-REDOR experiment can speed up the measurement by an order of magnitude. The effects from hetero-nuclear recoupling, the Bloch-Siegert shift and echo truncation to the signal acquisition are discussed and demonstrated.
Experimental realization of noise-induced adiabaticity in nuclear magnetic resonance
NASA Astrophysics Data System (ADS)
Wang, Bi-Xue; Xin, Tao; Kong, Xiang-Yu; Wei, Shi-Jie; Ruan, Dong; Long, Gui-Lu
2018-04-01
The adiabatic evolution is the dynamics of an instantaneous eigenstate of a slowly varing Hamiltonian. Recently, an interesting phenomenon shows up that white noises can enhance and even induce adiabaticity, which is in contrast to previous perception that environmental noises always modify and even ruin a designed adiabatic passage. We experimentally realized a noise-induced adiabaticity in a nuclear magnetic resonance system. Adiabatic Hadamard gate and entangled state are demonstrated. The effect of noise on adiabaticity is experimentally exhibited and compared with the noise-free process. We utilized a noise-injected method, which can be applied to other quantum systems.
Lallemand-Breitenbach, Valérie; de Thé, Hugues
2010-01-01
PML nuclear bodies are matrix-associated domains that recruit an astonishing variety of seemingly unrelated proteins. Since their discovery in the early 1960s, PML bodies have fascinated cell biologists because of their beauty and their tight association with cellular disorders. The identification of PML, a gene involved in an oncogenic chromosomal translocation, as the key organizer of these domains drew instant interest onto them. The multiple levels of PML body regulation by a specific posttranslational modification, sumoylation, have raised several unsolved issues. Functionally, PML bodies may sequester, modify or degrade partner proteins, but in many ways, PML bodies still constitute an enigma. PMID:20452955
Lallemand-Breitenbach, Valérie; de Thé, Hugues
2010-05-01
PML nuclear bodies are matrix-associated domains that recruit an astonishing variety of seemingly unrelated proteins. Since their discovery in the early 1960s, PML bodies have fascinated cell biologists because of their beauty and their tight association with cellular disorders. The identification of PML, a gene involved in an oncogenic chromosomal translocation, as the key organizer of these domains drew instant interest onto them. The multiple levels of PML body regulation by a specific posttranslational modification, sumoylation, have raised several unsolved issues. Functionally, PML bodies may sequester, modify or degrade partner proteins, but in many ways, PML bodies still constitute an enigma.
Morreale, A C; Novog, D R; Luxat, J C
2012-01-01
Technetium-99m is an important medical isotope utilized worldwide in nuclear medicine and is produced from the decay of its parent isotope, molybdenum-99. The online fueling capability and compact fuel of the CANDU(®)(1) reactor allows for the potential production of large quantities of (99)Mo. This paper proposes (99)Mo production strategies using modified target fuel bundles loaded into CANDU fuel channels. Using a small group of channels a yield of 89-113% of the weekly world demand for (99)Mo can be obtained. Copyright © 2011 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fang, Zhen F.; Gai, Hui; Huang, You Z.
2006-11-01
Embryonic stem cells were isolated from rabbit blastocysts derived from fertilization (conventional rbES cells), parthenogenesis (pES cells) and nuclear transfer (ntES cells), and propagated in a serum-free culture system. Rabbit ES (rbES) cells proliferated for a prolonged time in an undifferentiated state and maintained a normal karyotype. These cells grew in a monolayer with a high nuclear/cytoplasm ratio and contained a high level of alkaline phosphate activity. In addition, rbES cells expressed the pluripotent marker Oct-4, as well as EBAF2, FGF4, TDGF1, but not antigens recognized by antibodies against SSEA-1, SSEA-3, SSEA-4, TRA-1-10 and TRA-1-81. All 3 types of ESmore » cells formed embryoid bodies and generated teratoma that contained tissue types of all three germ layers. rbES cells exhibited a high cloning efficiency, were genetically modified readily and were used as nuclear donors to generate a viable rabbit through somatic cell nuclear transfer. In combination with genetic engineering, the ES cell technology should facilitate the creation of new rabbit lines.« less
Varadarajan, Padmapriya; Mahalingam, Sundarasamy; Liu, Peiyun; Ng, Sarah Boon Hsi; Gandotra, Sheetal; Dorairajoo, Desmond Suresh Kumar; Balasundaram, David
2005-04-01
We report that the fission yeast nucleoporin Nup124p is required for the nuclear import of both, retrotransposon Tf1-Gag as well as the retroviral HIV-1 Vpr. Failure to import Tf1-Gag into the nucleus in a nup124 null mutant resulted in complete loss of Tf1 transposition. Similarly, nuclear import of HIV-1 Vpr was impaired in nup124 null mutant strains and cells became resistant to Vpr's cell-killing activity. On the basis of protein domain similarity, the human nucleoporin Nup153 was identified as a putative homolog of Nup124p. We demonstrate that in vitro-translated Nup124p and Nup153 coimmunoprecipitate Tf1-Gag or HIV-1 Vpr. Though full-length Nup153 was unable to complement the Tf1 transposition defect in a nup124 null mutant, we provide evidence that both nucleoporins share a unique N-terminal domain, Nup124p(AA264-454) and Nup153(AA448-634) that is absolutely essential for Tf1 transposition. Epigenetic overexpression of this domain in a wild-type (nup124(+)) background blocked Tf1 activity implying that sequences from Nup124p and the human Nup153 challenged the same pathway affecting Tf1 transposition. Our results establish a unique relationship between two analogous nucleoporins Nup124p and Nup153 wherein the function of a common domain in retrotransposition is conserved.
Bubak, Andrew N; Como, Christina N; Blackmon, Anna M; Frietze, Seth; Mescher, Teresa; Jones, Dallas; Cohrs, Randall J; Paucek, Petr; Baird, Nicholas L; Nagel, Maria A
2018-05-19
Varicella zoster virus (VZV) can present as a myelopathy with spinal astrocyte infection. Recent studies support a role for the neurokinin-1 receptor (NK-1R) in virus infections, as well as for cytoskeletal alterations that may promote viral spread. Thus, we examined the role of NK-1R in VZV-infected primary human spinal astrocytes (HA-sps) to shed light on the pathogenesis of VZV myelopathy. Mock- and VZV-infected HA-sps were examined for substance P (subP) production, NK-1R localization, morphological changes and viral spread in the presence or absence of NK-1R antagonists, aprepitant and rolapitant. VZV infection of HA-sps induced nuclear localization of full-length and truncated NK-1R in the absence of the endogenous ligand, subP, and was associated with extensive lamellipodia formation and viral spread that was inhibited by NK-1R antagonists. We have identified a novel, subP-independent, proviral function of nuclear NK-1R associated with lamellipodia formation and viral spread that is distinct from subP-induced NK-1R cell membrane/cytoplasmic localization without lamellipodia formation. These results suggest that binding of a putative viral ligand to NK-1R produces a dramatically different NK-1R downstream effect than binding of subP. Finally, NK-1R antagonists aprepitant and rolapitant provide promising alternatives to nucleoside analogs in treating VZV infections, including myelopathy.
Huang, Xian-De; Wei, Guo-jian; Zhang, Hua; He, Mao-Xian
2015-01-01
Nuclear factor of activated T cells (NFAT) plays an important role in nonimmune cells and also in T cells and many other cells of the immune system, by regulating the expression of a variety of genes involved in the immune response, organ development, developmental apoptosis and angiogenesis. In the present study, the NFAT homology gene, PfNFAT, from the pearl oyster Pinctada fucata was cloned and its genomic structure and promoter were analyzed. PfNFAT encodes a putative protein of 1226 amino acids, and contains a highly conserved Rel homology region (RHR) with DNA-binding specificity, and a regulatory domain (NFAT homology region, NHR) containing a potent transactivation domain (TAD). The PfNFAT gene consists of 12 exons and 11 introns, and its promoter contains potential binding sites for transcription factors such as NF-κB (Nuclear factor κB), STATx (signal transducer and activator of transcription), AP-1 (activator protein-1) and Sox-5/9 (SRY type HMG box-5/9), MyoD (Myogenic Differentiation Antigen) and IRF (Interferon regulatory factor). Comparison and phylogenetic analysis revealed that PfNFAT shows high identity with other invertebrate NFAT, and clusters with the NFAT5 subgroup. Furthermore, gene expression analysis revealed that PfNFAT is involved in the immune response to lipopolysaccharide (LPS) and Polyinosinic-polycytidylic acid (poly I:C) stimulation and in the nucleus inserting operation. The study of PfNFAT may increase understanding of molluscan innate immunity. Copyright © 2014 Elsevier Ltd. All rights reserved.
Genomic characterization and regulation of CYP3a13: role of xenobiotics and nuclear receptors.
Anakk, Sayeepriyadarshini; Kalsotra, Auinash; Shen, Qi; Vu, Mary T; Staudinger, Jeffrey L; Davies, Peter J A; Strobel, Henry W
2003-09-01
We report that CYP3a13 gene, located on mouse chromosome 5, spans 27.5 Kb and contains 13 exons. The transcription start site is 35 bp upstream of the coding region and results in a 109 bp 5' untranslated region. CYP3a13 promoter shows putative binding sites for retinoid X receptor, pregnane X receptor, and estrogen receptor. CYP3a13 shows a broad tissue distribution with predominant expression in liver. Although CYP3a13 shares 92% nucleotide identity with the female-specific rat CYP3A9, its expression does not exhibit sexual dimorphism. Ligand activation of peroxisomal proliferator-activated receptor-gamma and retinoid X receptor inhibit expression of CYP3a13 at the transcription level in a tissue-specific manner. Another novel finding is hepatic induction of CYP3a13 by dexamethasone occurring only in pregnane X receptor null mice. We also report that pregnane X receptor is essential to maintain robust in vivo basal levels of CYP3a13 in contrast to CYP3a11. CYP3a13 protein expressed in vitro can metabolize clinically active drugs ethylmorphine and erythromycin, as well as benzphetamine. We conclude that CYP3a13 is regulated differentially by various nuclear receptors. In humans this may lead to altered drug metabolism, as many of the newly synthesized ligands/drugs targeted toward these nuclear receptors could influence CYP3A gene expression.
Chemical modifications of liquid natural rubber
NASA Astrophysics Data System (ADS)
Azhar, Nur Hanis Adila; Rasid, Hamizah Md; Yusoff, Siti Fairus M.
2016-11-01
Liquid natural rubber (LNR) was synthesized via photosentisized degradation of natural rubber (NR). LNR was modified into epoxidized liquid natural rubber (LENR) and hydroxylated liquid natural rubber (LNR-OH) using Na2WO4/CH3COOH/H2O2 catalytic system. Chemical structures of LNR and modified LNRs were characterized using Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) and 1H Nuclear Magnetic Resonance (NMR) spectroscopies. Integration of 1H NMR was used to calculate the epoxy content (%) of LENR. 1H NMR detected the formation of LNR-OH after prolonged heating and increased of catalyst in oxidation reaction.
NASA Technical Reports Server (NTRS)
Thomas, B. K.
1978-01-01
The Coulomb-modified form of the Glauber approximation is applied to the n = 2 and n = 3 excitation of hydrogenlike ions by incident electrons for various values of the target-ion nuclear charge Z sub n. The properly computed e(-)-He(+) 1s - 2s,2p Glauber predictions, including appropriate cascade effects, are compared with available experiment. The Z sub n dependence of the scaled integrated (over scattering angles) cross section is discussed, including the limit as Z sub n approaches infinity.
Nuclear processes associated with plant immunity and pathogen susceptibility
Motion, Graham B.; Amaro, Tiago M.M.M.; Kulagina, Natalja
2015-01-01
Plants are sessile organisms that have evolved exquisite and sophisticated mechanisms to adapt to their biotic and abiotic environment. Plants deploy receptors and vast signalling networks to detect, transmit and respond to a given biotic threat by inducing properly dosed defence responses. Genetic analyses and, more recently, next-generation -omics approaches have allowed unprecedented insights into the mechanisms that drive immunity. Similarly, functional genomics and the emergence of pathogen genomes have allowed reciprocal studies on the mechanisms governing pathogen virulence and host susceptibility, collectively allowing more comprehensive views on the processes that govern disease and resistance. Among others, the identification of secreted pathogen molecules (effectors) that modify immunity-associated processes has changed the plant–microbe interactions conceptual landscape. Effectors are now considered both important factors facilitating disease and novel probes, suited to study immunity in plants. In this review, we will describe the various mechanisms and processes that take place in the nucleus and help regulate immune responses in plants. Based on the premise that any process required for immunity could be targeted by pathogen effectors, we highlight and describe a number of functional assays that should help determine effector functions and their impact on immune-related processes. The identification of new effector functions that modify nuclear processes will help dissect nuclear signalling further and assist us in our bid to bolster immunity in crop plants. PMID:25846755
Nuclear processes associated with plant immunity and pathogen susceptibility.
Motion, Graham B; Amaro, Tiago M M M; Kulagina, Natalja; Huitema, Edgar
2015-07-01
Plants are sessile organisms that have evolved exquisite and sophisticated mechanisms to adapt to their biotic and abiotic environment. Plants deploy receptors and vast signalling networks to detect, transmit and respond to a given biotic threat by inducing properly dosed defence responses. Genetic analyses and, more recently, next-generation -omics approaches have allowed unprecedented insights into the mechanisms that drive immunity. Similarly, functional genomics and the emergence of pathogen genomes have allowed reciprocal studies on the mechanisms governing pathogen virulence and host susceptibility, collectively allowing more comprehensive views on the processes that govern disease and resistance. Among others, the identification of secreted pathogen molecules (effectors) that modify immunity-associated processes has changed the plant-microbe interactions conceptual landscape. Effectors are now considered both important factors facilitating disease and novel probes, suited to study immunity in plants. In this review, we will describe the various mechanisms and processes that take place in the nucleus and help regulate immune responses in plants. Based on the premise that any process required for immunity could be targeted by pathogen effectors, we highlight and describe a number of functional assays that should help determine effector functions and their impact on immune-related processes. The identification of new effector functions that modify nuclear processes will help dissect nuclear signalling further and assist us in our bid to bolster immunity in crop plants. © The Author 2015. Published by Oxford University Press.
Zhou, Qiyin; Wang, Wei; He, Xiangyu; Zhu, Xiaoyu; Shen, Yaoyao; Yu, Zhe; Wang, Xuexiang; Qi, Xuchen; Zhang, Xuan; Fan, Mingjie; Dai, Yu; Yang, Shuxu; Yan, Qingfeng
2014-01-01
The phenotypic manifestation of mitochondrial DNA (mtDNA) mutations can be modulated by nuclear genes and environmental factors. However, neither the interaction among these factors nor their underlying mechanisms are well understood. The yeast Saccharomyces cerevisiae mtDNA 15S rRNA C1477G mutation (PR) corresponds to the human 12S rRNA A1555G mutation. Here we report that a nuclear modifier gene mss1 mutation suppresses the neomycin-sensitivity phenotype of a yeast C1477G mutant in fermentable YPD medium. Functional assays show that the mitochondrial function of the yeast C1477G mutant was impaired severely in YPD medium with neomycin. Moreover, the mss1 mutation led to a significant increase in the steady-state level of HAP5 (heme activated protein), which greatly up-regulated the expression of glycolytic transcription factors RAP1, GCR1, and GCR2 and thus stimulated glycolysis. Furthermore, the high expression of the key glycolytic enzyme genes HXK2, PFK1 and PYK1 indicated that enhanced glycolysis not only compensated for the ATP reduction from oxidative phosphorylation (OXPHOS) in mitochondria, but also ensured the growth of the mss1(PR) mutant in YPD medium with neomycin. This study advances our understanding of the phenotypic manifestation of mtDNA mutations.
Modelling Psychological Responses to the Great East Japan Earthquake and Nuclear Incident
Goodwin, Robin; Takahashi, Masahito; Sun, Shaojing; Gaines, Stanley O.
2012-01-01
The Great East Japan (Tōhoku/Kanto) earthquake of March 2011was followed by a major tsunami and nuclear incident. Several previous studies have suggested a number of psychological responses to such disasters. However, few previous studies have modelled individual differences in the risk perceptions of major events, or the implications of these perceptions for relevant behaviours. We conducted a survey specifically examining responses to the Great Japan earthquake and nuclear incident, with data collected 11–13 weeks following these events. 844 young respondents completed a questionnaire in three regions of Japan; Miyagi (close to the earthquake and leaking nuclear plants), Tokyo/Chiba (approximately 220 km from the nuclear plants), and Western Japan (Yamaguchi and Nagasaki, some 1000 km from the plants). Results indicated significant regional differences in risk perception, with greater concern over earthquake risks in Tokyo than in Miyagi or Western Japan. Structural equation analyses showed that shared normative concerns about earthquake and nuclear risks, conservation values, lack of trust in governmental advice about the nuclear hazard, and poor personal control over the nuclear incident were positively correlated with perceived earthquake and nuclear risks. These risk perceptions further predicted specific outcomes (e.g. modifying homes, avoiding going outside, contemplating leaving Japan). The strength and significance of these pathways varied by region. Mental health and practical implications of these findings are discussed in the light of the continuing uncertainties in Japan following the March 2011 events. PMID:22666380